You are using an unsupported browser. Please upgrade your browser to a newer version to get the best experience on DrugBank.
Identification
NamePhenytoin
Accession NumberDB00252  (APRD00241)
TypeSmall Molecule
GroupsApproved, Vet Approved
DescriptionAn anticonvulsant that is used in a wide variety of seizures. It is also an anti-arrhythmic and a muscle relaxant. The mechanism of therapeutic action is not clear, although several cellular actions have been described including effects on ion channels, active transport, and general membrane stabilization. The mechanism of its muscle relaxant effect appears to involve a reduction in the sensitivity of muscle spindles to stretch. Phenytoin has been proposed for several other therapeutic uses, but its use has been limited by its many adverse effects and interactions with other drugs. [PubChem]
Structure
Thumb
Synonyms
5,5-Diphenyl-imidazolidine-2,4-dione
5,5-diphenylimidazolidine-2,4-dione
5,5-diphenyltetrahydro-1H-2,4-imidazoledione
5,5-Diphenyltetrahydro-1H-2,4-imidazoledione
Diphenylhydantoin
Fenitoina
Phentytoin
Phenytoine
Phenytoinum
External Identifiers Not Available
Approved Prescription Products
NameDosageStrengthRouteLabellerMarketing StartMarketing End
Dilantin - 100mgCapsule100 mgOralPfizer Canada Inc1951-12-31Not applicableCanada
Dilantin - 30mgCapsule30 mgOralPfizer Canada Inc1951-12-31Not applicableCanada
Dilantin InfatabsTablet50 mgOralPfizer Canada Inc1952-12-31Not applicableCanada
Dilantin Inj 50mg/mlLiquid250 mgIntramuscular; IntravenousParke Davis Division, Warner Lambert Canada Inc.1972-12-311996-09-10Canada
Dilantin-125Suspension125 mg/5mLOralParke Davis Div Of Pfizer Inc1953-01-06Not applicableUs
Dilantin-125 SuspensionSuspension125 mgOralPfizer Canada Inc1953-12-31Not applicableCanada
Dilantin-30 SuspensionSuspension30 mgOralPfizer Canada Inc1968-12-31Not applicableCanada
Novo-phenytoin Cap 100mgCapsule100 mgOralNovopharm Limited1966-12-31Not applicableCanada
PhenytoinSuspension125 mg/5mLOralGreenstone LLC2012-10-09Not applicableUs
Phenytoin Sodium Inj 50mg/ml USPSolution50 mgIntramuscular; IntravenousHospira Healthcare Corporation1989-12-31Not applicableCanada
Phenytoin Sodium Injection USPLiquid50 mgIntramuscular; IntravenousSandoz Canada Incorporated1988-12-31Not applicableCanada
Phenytoin Sodium Injection, USPSolution50 mgIntramuscular; IntravenousSterimax Inc2015-03-12Not applicableCanada
Taro-phenytoinSuspension125 mgOralTaro Pharmaceuticals Inc2005-05-03Not applicableCanada
Tremytoine Inj 50mg/mlLiquid50 mgIntramuscular; IntravenousOmega Laboratories Ltd1992-12-31Not applicableCanada
Approved Generic Prescription Products
NameDosageStrengthRouteLabellerMarketing StartMarketing End
DilantinCapsule, extended release100 mg/1OralCardinal Health1976-08-27Not applicableUs
DilantinTablet, chewable50 mg/1OralREMEDYREPACK INC.2011-08-182016-11-08Us
DilantinCapsule, extended release30 mg/1OralKAISER FOUNDATION HOSPITALS2009-09-20Not applicableUs
DilantinCapsule, extended release30 mg/1OralREMEDYREPACK INC.2011-05-052016-10-18Us
DilantinCapsule, extended release100 mg/1OralA S Medication Solutions Llc1976-08-27Not applicableUs
DilantinCapsule, extended release30 mg/1OralCarilion Materials Management1976-08-27Not applicableUs
DilantinCapsule, extended release100 mg/1OralParke Davis Div Of Pfizer Inc1976-08-27Not applicableUs
DilantinCapsule100 mg/1OralREMEDYREPACK INC.2011-07-08Not applicableUs
DilantinCapsule, extended release100 mg/1OralLake Erie Medical DBA Quality Care Products LLC1976-08-27Not applicableUs
DilantinCapsule, extended release100 mg/1OralPhysicians Total Care, Inc.1995-01-27Not applicableUs
DilantinCapsule, extended release30 mg/1OralAvera Mc Kennan Hospital2015-09-14Not applicableUs
DilantinCapsule, extended release100 mg/1OralAphena Pharma Solutions Tennessee, Inc.1976-08-27Not applicableUs
DilantinCapsule, extended release30 mg/1OralParke Davis Div Of Pfizer Inc1976-08-27Not applicableUs
DilantinCapsule, extended release100 mg/1OralA S Medication Solutions Llc1976-08-27Not applicableUs
DilantinCapsule, extended release30 mg/1OralPhysicians Total Care, Inc.2003-08-19Not applicableUs
DilantinCapsule, extended release30 mg/1OralREMEDYREPACK INC.2010-11-302016-10-13Us
Dilantin InfatabsTablet, chewable50 mg/1OralParke Davis Div Of Pfizer Inc1979-02-26Not applicableUs
Dilantin InfatabsTablet, chewable50 mg/1OralCardinal Health1979-02-26Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralState of Florida DOH Central Pharmacy2014-01-01Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralREMEDYREPACK INC.2014-08-25Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralA S Medication Solutions2009-12-16Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralPd Rx Pharmaceuticals, Inc.2009-12-16Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralPd Rx Pharmaceuticals, Inc.2008-01-30Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralA S Medication Solutions2009-12-16Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralAmneal Pharmaceuticals of New York, LLC2009-12-16Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralWockhardt USA LLC.2008-01-30Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralREMEDYREPACK INC.2012-12-26Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralWockhardt Limited2008-01-30Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralAmerican Health Packaging2013-07-19Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralREMEDYREPACK INC.2013-04-092016-11-05Us
Extended Phenytoin SodiumCapsule, extended release100 mg/1OralMarlex Pharmaceuticals Inc2015-08-01Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralMajor Pharmaceuticals2009-12-16Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralAurobindo Pharma Limited2015-06-10Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralTYA Pharmaceuticals2008-01-30Not applicableUs
Extended Phenytoin SodiumCapsule100 mg/1OralREMEDYREPACK INC.2013-05-08Not applicableUs
PhenytekCapsule, extended release300 mg/1OralClinical Solutions Wholesale2001-12-10Not applicableUs
PhenytekCapsule, extended release200 mg/1OralMylan Pharmaceuticals Inc.2001-12-10Not applicableUs
PhenytekCapsule, extended release300 mg/1OralMylan Pharmaceuticals Inc.2001-12-10Not applicableUs
PhenytoinSuspension100 mg/4mLOralPrecision Dose Inc.2004-02-052016-02-05Us
PhenytoinSuspension125 mg/5mLOralMorton Grove Pharmaceuticals, Inc.2002-06-24Not applicableUs
PhenytoinTablet, chewable50 mg/1OralMylan Institutional Inc.2012-12-18Not applicableUs
PhenytoinSuspension125 mg/5mLOralPhysicians Total Care, Inc.2006-12-19Not applicableUs
PhenytoinSuspension125 mg/5mLOralVista Pharm Inc.2010-05-10Not applicableUs
PhenytoinSuspension125 mg/5mLOralTaro Pharmaceuticals U.S.A., Inc.2004-04-08Not applicableUs
PhenytoinTablet, chewable50 mg/1OralMylan Pharmaceuticals Inc.2012-12-26Not applicableUs
PhenytoinSuspension125 mg/5mLOralVista Pharm Inc.2005-08-18Not applicableUs
PhenytoinTablet, chewable50 mg/1OralNcs Health Care Of Ky, Inc Dba Vangard Labs2012-12-26Not applicableUs
PhenytoinTablet, chewable50 mg/1OralAmerican Health Packaging2015-09-01Not applicableUs
PhenytoinSuspension125 mg/5mLOralLehigh Valley Technologies, Inc.2014-04-01Not applicableUs
PhenytoinTablet, chewable50 mg/1OralCore Pharma, Llc2016-02-28Not applicableUs
PhenytoinSuspension125 mg/5mLOralAtlantic Biologicals Corps2002-06-24Not applicableUs
PhenytoinSuspension125 mg/5mLOralAtlantic Biologicals Corps2004-04-08Not applicableUs
PhenytoinTablet, chewable50 mg/1OralCardinal Health2012-12-26Not applicableUs
PhenytoinSuspension125 mg/5mLOralActavis Mid Atlantic LLC2009-03-02Not applicableUs
PhenytoinTablet, chewable50 mg/1OralTaro Pharmaceuticals U.S.A., Inc2014-04-17Not applicableUs
Phenytoin ERCapsule100 mg/1OralSTAT Rx USA LLC2009-11-20Not applicableUs
Phenytoin InfatabsTablet, chewable50 mg/1OralGreenstone LLC2012-12-27Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralNcs Health Care Of Ky, Inc Dba Vangard Labs2009-11-20Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralREMEDYREPACK INC.2013-08-27Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralCardinal Health2006-09-05Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralTYA Pharmaceuticals2006-09-05Not applicableUs
Phenytoin SodiumInjection50 mg/mLIntramuscular; IntravenousWest Ward Pharmaceuticals Corp.1975-07-16Not applicableUs
Phenytoin SodiumInjection, solution50 mg/mLIntramuscular; IntravenousX Gen Pharmaceuticals, Inc.2011-05-02Not applicableUs
Phenytoin SodiumCapsule, extended release300 mg/1OralSun Pharmaceutical Industries Limited2008-06-30Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralAphena Pharma Solutions Tennessee, Llc1999-01-05Not applicableUs
Phenytoin SodiumInjection, solution50 mg/mLIntramuscular; IntravenousGeneral Injectables & Vaccines, Inc2010-08-01Not applicableUs
Phenytoin SodiumInjection50 mg/mLIntravenousCardinal Health2006-10-01Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralLake Erie Medical DBA Quality Care Products LLC2006-12-12Not applicableUs
Phenytoin SodiumInjection50 mg/mLIntramuscular; IntravenousCardinal Health1975-07-16Not applicableUs
Phenytoin SodiumInjection50 mg/mLIntramuscular; IntravenousWest Ward Pharmaceuticals Corp.1975-07-16Not applicableUs
Phenytoin SodiumInjection, solution50 mg/mLIntramuscular; IntravenousGeneral Injectables & Vaccines, Inc2010-08-01Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralMylan Pharmaceuticals Inc.1999-01-05Not applicableUs
Phenytoin SodiumInjection, solution50 mg/mLIntramuscular; IntravenousCardinal Health2011-05-02Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1Oralbryant ranch prepack2011-07-07Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralREMEDYREPACK INC.2013-03-20Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralPhysicians Total Care, Inc.2007-07-12Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralContract Pharmacy Services Pa2010-04-06Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralTaro Pharmaceuticals U.S.A., Inc.2006-09-05Not applicableUs
Phenytoin SodiumInjection, solution50 mg/mLIntramuscular; IntravenousHospira, Inc.1987-12-18Not applicableUs
Phenytoin SodiumInjection, solution50 mg/mLIntramuscular; IntravenousGeneral Injectables & Vaccines, Inc2011-04-12Not applicableUs
Phenytoin SodiumInjection, solution50 mg/mLIntramuscular; IntravenousHospira, Inc.1987-03-17Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralClinical Solutions Wholesale2006-12-12Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralUpsher Smith Laboratories, Inc.2006-09-05Not applicableUs
Phenytoin SodiumCapsule, extended release200 mg/1OralSun Pharmaceutical Industries Limited2008-06-30Not applicableUs
Phenytoin SodiumInjection50 mg/mLIntramuscular; IntravenousWest Ward Pharmaceuticals Corp.1975-07-16Not applicableUs
Phenytoin SodiumInjection, solution50 mg/mLIntramuscular; IntravenousGeneral Injectables & Vaccines, Inc2010-03-01Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralCardinal Health2011-01-28Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralNcs Health Care Of Ky, Inc Dba Vangard Labs2006-09-05Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralMylan Institutional Inc.1999-05-01Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralState of Florida DOH Central Pharmacy2009-07-01Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralSun Pharmaceutical Industries Limited2006-12-12Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralMc Kesson Contract Packaging2011-09-19Not applicableUs
Phenytoin SodiumCapsule100 mg/1OralDIRECT RX2014-01-01Not applicableUs
Phenytoin SodiumInjection, solution250 mg/5mLIntramuscular; IntravenousGeneral Injectables & Vaccines, Inc.2011-08-30Not applicableUs
Phenytoin SodiumInjection50 mg/mLIntravenousCardinal Health2006-10-01Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralRebel Distributors Corp2006-09-05Not applicableUs
Phenytoin SodiumInjection50 mg/mLIntramuscular; IntravenousWest Ward Pharmaceuticals Corp.1975-07-16Not applicableUs
Phenytoin SodiumCapsule, extended release100 mg/1OralA S Medication Solutions2006-12-12Not applicableUs
Phenytoin Sodium ExtendedCapsule100 mg/1OralAv Pak2016-06-07Not applicableUs
Approved Over the Counter ProductsNot Available
Unapproved/Other Products Not Available
International Brands
NameCompany
Epanutin Pfizer
EptoinNot Available
Brand mixtures
NameLabellerIngredients
Dilantin W Phenobarbital 15mgParke Davis Division, Warner Lambert Canada Inc.
Dilantin W Phenobarbital 30mg CapParke Davis Division, Warner Lambert Canada Inc.
Salts
Name/CASStructureProperties
Phenytoin sodium
630-93-3
Thumb
  • InChI Key: FJPYVLNWWICYDW-UHFFFAOYSA-M
  • Monoisotopic Mass: 274.071822281
  • Average Mass: 274.2498
DBSALT000139
Categories
UNII6158TKW0C5
CAS number57-41-0
WeightAverage: 252.268
Monoisotopic: 252.089877638
Chemical FormulaC15H12N2O2
InChI KeyCXOFVDLJLONNDW-UHFFFAOYSA-N
InChI
InChI=1S/C15H12N2O2/c18-13-15(17-14(19)16-13,11-7-3-1-4-8-11)12-9-5-2-6-10-12/h1-10H,(H2,16,17,18,19)
IUPAC Name
5,5-diphenylimidazolidine-2,4-dione
SMILES
O=C1NC(=O)C(N1)(C1=CC=CC=C1)C1=CC=CC=C1
Pharmacology
IndicationFor the control of generalized tonic-clonic (grand mal) and complex partial (psychomotor, temporal lobe) seizures and prevention and treatment of seizures occurring during or following neurosurgery.
Structured Indications
PharmacodynamicsPhenytoin is an antiepileptic drug which can be useful in the treatment of epilepsy. The primary site of action appears to be the motor cortex where spread of seizure activity is inhibited. Phenytoin reduces the maximal activity of brain stem centers responsible for the tonic phase of tonic-clonic (grand mal) seizures. Phenytoin acts to dampen the unwanted, runaway brain activity seen in seizure by reducing electrical conductance among brain cells. It lacks the sedation effects associated with phenobarbital. There are some indications that phenytoin has other effects, including anxiety control and mood stabilization, although it has never been approved for those purposes by the FDA. Phenytoin is primarily metabolized by CYP2C9.
Mechanism of actionPhenytoin acts on sodium channels on the neuronal cell membrane, limiting the spread of seizure activity and reducing seizure propagation. By promoting sodium efflux from neurons, phenytoin tends to stabilize the threshold against hyperexcitability caused by excessive stimulation or environmental changes capable of reducing membrane sodium gradient. This includes the reduction of post-tetanic potentiation at synapses. Loss of post-tetanic potentiation prevents cortical seizure foci from detonating adjacent cortical areas.
TargetKindPharmacological actionActionsOrganismUniProt ID
Sodium channel protein type 5 subunit alphaProteinyes
inhibitor
HumanQ14524 details
Sodium channel protein type 1 subunit alphaProteinyes
inhibitor
HumanP35498 details
Related Articles
AbsorptionBioavailability 70-100% oral, 24.4% rectal. Rapid rate of absorption with peak blood concentration expected in 1½ to 3 hours.
Volume of distributionNot Available
Protein bindingHighly protein bound, 90%
Metabolism

Primarily hepatic. The majority of the dose (up to 90%) is metabolized to 5-(4'-hydroxyphenyl)-5-phenylhydantoin (p-HPPH). This metabolite undergoes further glucuronidation and is excreted into the urine. CYP2C19 and CYP2C9 catalyze the aforementioned reaction.

SubstrateEnzymesProduct
Phenytoin
3',4'-DihydrodiolDetails
Phenytoin
3'-HPPHDetails
Phenytoin
4'-HPPHDetails
Phenytoin
Phenytoin arene-oxideDetails
Phenytoin
Not Available
Phenytoin catecholDetails
Phenytoin
Not Available
Phenytoin quinoneDetails
Phenytoin catechol
Phenytoin methylcatecholDetails
Phenytoin arene-oxide
Phenytoin dihydrodiolDetails
Phenytoin arene-oxide
Not Available
HydroxyphenytoinDetails
Hydroxyphenytoin
Phenytoin catecholDetails
Phenytoin catechol
Phenytoin quinoneDetails
Hydroxyphenytoin
Hydroxyphenytoin-O-glucuronideDetails
3'-HPPH
3',4'-diHPPHDetails
4'-HPPH
3',4'-diHPPHDetails
Route of eliminationMost of the drug is excreted in the bile as inactive metabolites which are then reabsorbed from the intestinal tract and excreted in the urine. Urinary excretion of phenytoin and its metabolites occurs partly with glomerular filtration but, more importantly, by tubular secretion.
Half life22 hours (range of 7 to 42 hours)
ClearanceNot Available
ToxicityOral, mouse: LD50 = 150 mg/kg; Oral, rat: LD50 = 1635 mg/kg. Symptoms of overdose include coma, difficulty in pronouncing words correctly, involuntary eye movement, lack of muscle coordination, low blood pressure, nausea, sluggishness, slurred speech, tremors, and vomiting.
Affected organisms
  • Humans and other mammals
Pathways
PathwayCategorySMPDB ID
Fosphenytoin (Antiarrhythmic) Action PathwayDrug actionSMP00326
Fosphenytoin (Antiarrhythmic) Metabolism PathwayDrug metabolismSMP00618
Phenytoin (Antiarrhythmic) Action PathwayDrug actionSMP00327
SNP Mediated Effects
Interacting Gene/EnzymeSNP RS IDAllele nameDefining changeEffectReference(s)
Cytochrome P450 2C9
Gene symbol: CYP2C9
UniProt: P11712
rs1057910 CYP2C9*1C AllelePoor drug metabolizer, lower dose requirements15805193
Multidrug resistance protein 1
Gene symbol: ABCB1
UniProt: P08183
rs1045642 MDR1*TT Allele (C3435T)Increased phenytoin effects due to higher plasma phenytoin levels11908757
SNP Mediated Adverse Drug ReactionsNot Available
Interactions
Drug Interactions
DrugInteractionDrug group
1,1,1,2 TetrafluoroethaneThe risk or severity of adverse effects can be increased when Phenytoin is combined with 1,1,1,2 Tetrafluoroethane.Investigational
16-BromoepiandrosteroneThe serum concentration of 16-Bromoepiandrosterone can be decreased when it is combined with Phenytoin.Investigational
19-norandrostenedioneThe serum concentration of 19-norandrostenedione can be decreased when it is combined with Phenytoin.Experimental, Illicit
2-HYDROXY-1,4-NAPHTHOQUINONEThe serum concentration of Phenytoin can be increased when it is combined with 2-HYDROXY-1,4-NAPHTHOQUINONE.Experimental
2-mercaptobenzothiazoleThe serum concentration of Phenytoin can be increased when it is combined with 2-mercaptobenzothiazole.Vet Approved
2,5-Dimethoxy-4-ethylamphetamineThe serum concentration of Phenytoin can be decreased when it is combined with 2,5-Dimethoxy-4-ethylamphetamine.Experimental, Illicit
3,4-MethylenedioxyamphetamineThe serum concentration of Phenytoin can be decreased when it is combined with 3,4-Methylenedioxyamphetamine.Experimental, Illicit
3,4-MethylenedioxymethamphetamineThe serum concentration of Phenytoin can be decreased when it is combined with 3,4-Methylenedioxymethamphetamine.Experimental, Illicit
4-AndrostenedioneThe serum concentration of 4-Androstenedione can be decreased when it is combined with Phenytoin.Experimental, Illicit
4-Bromo-2,5-dimethoxyamphetamineThe serum concentration of Phenytoin can be decreased when it is combined with 4-Bromo-2,5-dimethoxyamphetamine.Experimental, Illicit
5-androstenedioneThe serum concentration of 5-androstenedione can be decreased when it is combined with Phenytoin.Experimental, Illicit
7-NitroindazoleThe risk or severity of adverse effects can be increased when 7-Nitroindazole is combined with Phenytoin.Experimental
AbirateroneThe serum concentration of Abiraterone can be decreased when it is combined with Phenytoin.Approved
AceclofenacThe metabolism of Aceclofenac can be increased when combined with Phenytoin.Approved
AcenocoumarolPhenytoin may increase the anticoagulant activities of Acenocoumarol.Approved
AcepromazineThe risk or severity of adverse effects can be increased when Acepromazine is combined with Phenytoin.Approved, Vet Approved
AceprometazineThe risk or severity of adverse effects can be increased when Aceprometazine is combined with Phenytoin.Approved
AcetaminophenThe serum concentration of Acetaminophen can be decreased when it is combined with Phenytoin.Approved
AcetazolamideThe risk or severity of adverse effects can be increased when Acetazolamide is combined with Phenytoin.Approved, Vet Approved
Acetylsalicylic acidThe metabolism of Acetylsalicylic acid can be increased when combined with Phenytoin.Approved, Vet Approved
AdinazolamThe metabolism of Adinazolam can be increased when combined with Phenytoin.Approved
adipiplonThe risk or severity of adverse effects can be increased when adipiplon is combined with Phenytoin.Investigational
AfatinibThe serum concentration of Phenytoin can be increased when it is combined with Afatinib.Approved
AgomelatineThe risk or severity of adverse effects can be increased when Agomelatine is combined with Phenytoin.Approved, Investigational
AlbendazoleThe serum concentration of the active metabolites of Albendazole can be reduced when Albendazole is used in combination with Phenytoin resulting in a loss in efficacy.Approved, Vet Approved
AlclometasoneThe metabolism of Alclometasone can be increased when combined with Phenytoin.Approved
AldosteroneThe serum concentration of Phenytoin can be decreased when it is combined with Aldosterone.Experimental
AlectinibThe serum concentration of Phenytoin can be increased when it is combined with Alectinib.Approved
AlfaxaloneThe risk or severity of adverse effects can be increased when Alfaxalone is combined with Phenytoin.Vet Approved
AlfentanilThe metabolism of Alfentanil can be increased when combined with Phenytoin.Approved, Illicit
AlfuzosinThe metabolism of Alfuzosin can be increased when combined with Phenytoin.Approved, Investigational
AliskirenThe metabolism of Aliskiren can be increased when combined with Phenytoin.Approved, Investigational
AllylestrenolThe metabolism of Allylestrenol can be increased when combined with Phenytoin.Approved
AlmotriptanThe metabolism of Almotriptan can be increased when combined with Phenytoin.Approved, Investigational
AlogliptinThe metabolism of Alogliptin can be increased when combined with Phenytoin.Approved
AlosetronThe metabolism of Alosetron can be increased when combined with Phenytoin.Approved, Withdrawn
AlphacetylmethadolThe risk or severity of adverse effects can be increased when Alphacetylmethadol is combined with Phenytoin.Experimental, Illicit
AlprazolamThe serum concentration of Phenytoin can be increased when it is combined with Alprazolam.Approved, Illicit, Investigational
AmantadineThe serum concentration of Phenytoin can be increased when it is combined with Amantadine.Approved
AmbrisentanThe metabolism of Ambrisentan can be increased when combined with Phenytoin.Approved, Investigational
AmbroxolThe metabolism of Ambroxol can be increased when combined with Phenytoin.Approved
Ambroxol acefyllinateThe serum concentration of Ambroxol acefyllinate can be decreased when it is combined with Phenytoin.Experimental
AmcinonideThe serum concentration of Amcinonide can be decreased when it is combined with Phenytoin.Approved
Aminohippuric acidThe serum concentration of Phenytoin can be increased when it is combined with Aminohippuric acid.Approved
AminophenazoneThe metabolism of Aminophenazone can be increased when combined with Phenytoin.Approved, Withdrawn
AminophyllineThe serum concentration of Aminophylline can be decreased when it is combined with Phenytoin.Approved
AmiodaroneThe serum concentration of Amiodarone can be decreased when it is combined with Phenytoin.Approved, Investigational
AmisulprideThe risk or severity of adverse effects can be increased when Amisulpride is combined with Phenytoin.Approved, Investigational
AmitriptylineThe metabolism of Amitriptyline can be increased when combined with Phenytoin.Approved
AmlodipineThe serum concentration of Phenytoin can be increased when it is combined with Amlodipine.Approved
AmobarbitalThe risk or severity of adverse effects can be increased when Amobarbital is combined with Phenytoin.Approved, Illicit
AmodiaquineThe metabolism of Amodiaquine can be increased when combined with Phenytoin.Approved
AmorolfineThe serum concentration of Phenytoin can be increased when it is combined with Amorolfine.Approved
AmoxapineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Amoxapine.Approved
AmoxicillinThe metabolism of Amoxicillin can be increased when combined with Phenytoin.Approved, Vet Approved
AmperozideThe risk or severity of adverse effects can be increased when Amperozide is combined with Phenytoin.Experimental
AmphetamineThe serum concentration of Phenytoin can be decreased when it is combined with Amphetamine.Approved, Illicit
Amphotericin BThe serum concentration of Phenytoin can be increased when it is combined with Amphotericin B.Approved, Investigational
AmprenavirThe metabolism of Amprenavir can be increased when combined with Phenytoin.Approved
AmrinoneThe serum concentration of Phenytoin can be increased when it is combined with Amrinone.Approved
AmsacrineThe serum concentration of Phenytoin can be increased when it is combined with Amsacrine.Approved
AN2690The serum concentration of Phenytoin can be increased when it is combined with AN2690.Investigational
AnecortaveThe serum concentration of Anecortave can be decreased when it is combined with Phenytoin.Investigational
AnidulafunginThe serum concentration of Phenytoin can be increased when it is combined with Anidulafungin.Approved, Investigational
AntipyrineThe metabolism of Antipyrine can be increased when combined with Phenytoin.Approved
ApixabanThe serum concentration of Apixaban can be decreased when it is combined with Phenytoin.Approved
ApremilastThe serum concentration of Apremilast can be decreased when it is combined with Phenytoin.Approved, Investigational
AprepitantThe serum concentration of Phenytoin can be increased when it is combined with Aprepitant.Approved, Investigational
Arachidonic AcidThe metabolism of Arachidonic Acid can be increased when combined with Phenytoin.Experimental
ArformoterolThe metabolism of Arformoterol can be increased when combined with Phenytoin.Approved, Investigational
ArgatrobanThe metabolism of Argatroban can be increased when combined with Phenytoin.Approved, Investigational
AripiprazoleThe serum concentration of Aripiprazole can be decreased when it is combined with Phenytoin.Approved, Investigational
ArmodafinilThe metabolism of Phenytoin can be decreased when combined with Armodafinil.Approved, Investigational
ArtemetherThe serum concentration of the active metabolites of Artemether can be reduced when Artemether is used in combination with Phenytoin resulting in a loss in efficacy.Approved
ArticaineThe risk or severity of adverse effects can be increased when Articaine is combined with Phenytoin.Approved
AsenapineThe metabolism of Asenapine can be increased when combined with Phenytoin.Approved
AstemizoleThe metabolism of Astemizole can be increased when combined with Phenytoin.Approved, Withdrawn
AtazanavirThe metabolism of Atazanavir can be increased when combined with Phenytoin.Approved, Investigational
AtenololThe serum concentration of Phenytoin can be increased when it is combined with Atenolol.Approved
AtomoxetineThe metabolism of Atomoxetine can be increased when combined with Phenytoin.Approved
AtorvastatinThe serum concentration of Atorvastatin can be decreased when it is combined with Phenytoin.Approved
Atracurium besylatePhenytoin may decrease the neuromuscular blocking activities of Atracurium besylate.Approved
AvanafilThe metabolism of Avanafil can be increased when combined with Phenytoin.Approved
AxitinibThe serum concentration of Axitinib can be decreased when it is combined with Phenytoin.Approved, Investigational
AzaperoneThe risk or severity of adverse effects can be increased when Azaperone is combined with Phenytoin.Vet Approved
AzelastinePhenytoin may increase the central nervous system depressant (CNS depressant) activities of Azelastine.Approved
AzelastineThe metabolism of Azelastine can be increased when combined with Phenytoin.Approved
AzelnidipineThe serum concentration of Phenytoin can be increased when it is combined with Azelnidipine.Approved
AzimilideThe serum concentration of Phenytoin can be increased when it is combined with Azimilide.Investigational
AzithromycinThe metabolism of Azithromycin can be increased when combined with Phenytoin.Approved
BaclofenThe risk or severity of adverse effects can be increased when Baclofen is combined with Phenytoin.Approved
Bafilomycin A1The serum concentration of Phenytoin can be increased when it is combined with Bafilomycin A1.Experimental
BanoxantroneThe metabolism of Banoxantrone can be increased when combined with Phenytoin.Investigational
BarbitalThe risk or severity of adverse effects can be increased when Barbital is combined with Phenytoin.Illicit
BarnidipineThe serum concentration of Phenytoin can be increased when it is combined with Barnidipine.Approved
BazedoxifeneThe serum concentration of Bazedoxifene can be decreased when it is combined with Phenytoin.Approved, Investigational
BeclomethasoneThe serum concentration of Beclomethasone can be decreased when it is combined with Phenytoin.Investigational
Beclomethasone dipropionateThe serum concentration of Beclomethasone dipropionate can be decreased when it is combined with Phenytoin.Approved, Investigational
BedaquilineThe serum concentration of Bedaquiline can be decreased when it is combined with Phenytoin.Approved
BenidipineThe serum concentration of Phenytoin can be increased when it is combined with Benidipine.Approved
BenperidolThe risk or severity of adverse effects can be increased when Phenytoin is combined with Benperidol.Investigational
BenzatropineThe metabolism of Benzatropine can be increased when combined with Phenytoin.Approved
BenzocaineThe serum concentration of Phenytoin can be increased when it is combined with Benzocaine.Approved
Benzoic AcidThe serum concentration of Phenytoin can be increased when it is combined with Benzoic Acid.Approved
BenzphetamineThe serum concentration of Phenytoin can be decreased when it is combined with Benzphetamine.Approved, Illicit
Benzyl alcoholThe metabolism of Benzyl alcohol can be increased when combined with Phenytoin.Approved
BepridilThe serum concentration of Phenytoin can be increased when it is combined with Bepridil.Approved, Withdrawn
BeraprostThe metabolism of Beraprost can be increased when combined with Phenytoin.Investigational
BetamethasoneThe serum concentration of Betamethasone can be decreased when it is combined with Phenytoin.Approved, Vet Approved
BexaroteneThe metabolism of Bexarotene can be increased when combined with Phenytoin.Approved, Investigational
BezafibrateThe metabolism of Bezafibrate can be increased when combined with Phenytoin.Approved
BicalutamideThe metabolism of Bicalutamide can be increased when combined with Phenytoin.Approved
BifonazoleThe serum concentration of Phenytoin can be increased when it is combined with Bifonazole.Approved
BiperidenThe serum concentration of Phenytoin can be increased when it is combined with Biperiden.Approved
BisoprololThe metabolism of Bisoprolol can be increased when combined with Phenytoin.Approved
BleomycinThe serum concentration of Phenytoin can be decreased when it is combined with Bleomycin.Approved
BoceprevirThe serum concentration of Boceprevir can be decreased when it is combined with Phenytoin.Approved
BortezomibThe serum concentration of Bortezomib can be decreased when it is combined with Phenytoin.Approved, Investigational
BosentanThe serum concentration of Phenytoin can be decreased when it is combined with Bosentan.Approved, Investigational
BosutinibThe serum concentration of Bosutinib can be decreased when it is combined with Phenytoin.Approved
Brentuximab vedotinThe serum concentration of Brentuximab vedotin can be decreased when it is combined with Phenytoin.Approved
BrexpiprazoleThe serum concentration of Brexpiprazole can be decreased when it is combined with Phenytoin.Approved
BrimonidineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Brimonidine.Approved
BrimonidineBrimonidine may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.Approved
BrinzolamideThe metabolism of Brinzolamide can be increased when combined with Phenytoin.Approved
BromazepamThe serum concentration of Phenytoin can be increased when it is combined with Bromazepam.Approved, Illicit
BromocriptineThe metabolism of Bromocriptine can be increased when combined with Phenytoin.Approved, Investigational
BrompheniramineThe metabolism of Brompheniramine can be increased when combined with Phenytoin.Approved
BrotizolamThe risk or severity of adverse effects can be increased when Brotizolam is combined with Phenytoin.Approved, Withdrawn
BudesonideThe metabolism of Budesonide can be increased when combined with Phenytoin.Approved
BumetanidePhenytoin may decrease the diuretic activities of Bumetanide.Approved
BupivacaineThe metabolism of Bupivacaine can be increased when combined with Phenytoin.Approved, Investigational
BuprenorphinePhenytoin may increase the central nervous system depressant (CNS depressant) activities of Buprenorphine.Approved, Illicit, Investigational, Vet Approved
BupropionThe metabolism of Bupropion can be increased when combined with Phenytoin.Approved
BuspironeThe metabolism of Buspirone can be increased when combined with Phenytoin.Approved, Investigational
BusulfanThe serum concentration of Busulfan can be decreased when it is combined with Phenytoin.Approved, Investigational
ButabarbitalThe risk or severity of adverse effects can be increased when Butabarbital is combined with Phenytoin.Approved, Illicit
ButacaineThe risk or severity of adverse effects can be increased when Butacaine is combined with Phenytoin.Vet Approved
ButalbitalThe risk or severity of adverse effects can be increased when Butalbital is combined with Phenytoin.Approved, Illicit
ButambenThe risk or severity of adverse effects can be increased when Butamben is combined with Phenytoin.Approved
ButenafineThe serum concentration of Phenytoin can be increased when it is combined with Butenafine.Approved
ButethalThe risk or severity of adverse effects can be increased when Butethal is combined with Phenytoin.Approved, Illicit
ButoconazoleThe serum concentration of Phenytoin can be increased when it is combined with Butoconazole.Approved
ButorphanolThe risk or severity of adverse effects can be increased when Butorphanol is combined with Phenytoin.Approved, Illicit, Vet Approved
CabazitaxelThe metabolism of Cabazitaxel can be increased when combined with Phenytoin.Approved
CabergolineThe metabolism of Cabergoline can be increased when combined with Phenytoin.Approved
CabozantinibThe serum concentration of Cabozantinib can be decreased when it is combined with Phenytoin.Approved
CaffeineThe metabolism of Caffeine can be increased when combined with Phenytoin.Approved
CaiThe serum concentration of Phenytoin can be increased when it is combined with Cai.Investigational
CalcitriolThe metabolism of Calcitriol can be increased when combined with Phenytoin.Approved, Nutraceutical
CamazepamThe serum concentration of Phenytoin can be increased when it is combined with Camazepam.Approved, Illicit
CanagliflozinThe serum concentration of Canagliflozin can be decreased when it is combined with Phenytoin.Approved
CandesartanThe metabolism of Candesartan can be increased when combined with Phenytoin.Approved
CandicidinThe serum concentration of Phenytoin can be increased when it is combined with Candicidin.Withdrawn
CannabidiolThe serum concentration of Cannabidiol can be decreased when it is combined with Phenytoin.Approved, Investigational
CapecitabineThe serum concentration of Phenytoin can be increased when it is combined with Capecitabine.Approved, Investigational
CaptoprilThe serum concentration of Phenytoin can be increased when it is combined with Captopril.Approved
CarbamazepineThe serum concentration of Phenytoin can be decreased when it is combined with Carbamazepine.Approved, Investigational
CarbinoxamineThe metabolism of Carbinoxamine can be increased when combined with Phenytoin.Approved
CarboplatinThe serum concentration of Phenytoin can be decreased when it is combined with Carboplatin.Approved
CarfentanilThe risk or severity of adverse effects can be increased when Carfentanil is combined with Phenytoin.Illicit, Vet Approved
CariprazineThe metabolism of Cariprazine can be increased when combined with Phenytoin.Approved
CarisoprodolThe metabolism of Carisoprodol can be increased when combined with Phenytoin.Approved
CarvedilolThe metabolism of Carvedilol can be increased when combined with Phenytoin.Approved, Investigational
CaspofunginThe serum concentration of Caspofungin can be decreased when it is combined with Phenytoin.Approved
CefazolinThe protein binding of Phenytoin can be decreased when combined with Cefazolin.Approved
CelecoxibThe metabolism of Celecoxib can be increased when combined with Phenytoin.Approved, Investigational
CeliprololThe metabolism of Celiprolol can be increased when combined with Phenytoin.Approved, Investigational
CephalexinThe metabolism of Cephalexin can be increased when combined with Phenytoin.Approved, Vet Approved
CeritinibThe serum concentration of Ceritinib can be decreased when it is combined with Phenytoin.Approved
CerivastatinThe serum concentration of Cerivastatin can be decreased when it is combined with Phenytoin.Withdrawn
CeruleninThe serum concentration of Phenytoin can be increased when it is combined with Cerulenin.Approved
CetirizineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Cetirizine.Approved
CevimelineThe metabolism of Cevimeline can be increased when combined with Phenytoin.Approved
Chenodeoxycholic acidThe metabolism of Chenodeoxycholic acid can be increased when combined with Phenytoin.Approved
Chloral hydrateThe risk or severity of adverse effects can be increased when Chloral hydrate is combined with Phenytoin.Approved, Illicit, Vet Approved
ChloramphenicolThe metabolism of Phenytoin can be decreased when combined with Chloramphenicol.Approved, Vet Approved
ChlordiazepoxideThe serum concentration of Phenytoin can be increased when it is combined with Chlordiazepoxide.Approved, Illicit
ChlormezanoneThe risk or severity of adverse effects can be increased when Chlormezanone is combined with Phenytoin.Approved, Withdrawn
ChloroprocaineThe risk or severity of adverse effects can be increased when Chloroprocaine is combined with Phenytoin.Approved
ChloroquineThe metabolism of Chloroquine can be increased when combined with Phenytoin.Approved, Vet Approved
ChlorotrianiseneThe therapeutic efficacy of Chlorotrianisene can be decreased when used in combination with Phenytoin.Withdrawn
ChloroxineThe serum concentration of Phenytoin can be increased when it is combined with Chloroxine.Approved
ChlorphenamineThe serum concentration of Phenytoin can be increased when it is combined with Chlorphenamine.Approved
ChlorphentermineThe serum concentration of Phenytoin can be decreased when it is combined with Chlorphentermine.Illicit, Withdrawn
ChlorpromazineThe metabolism of Chlorpromazine can be increased when combined with Phenytoin.Approved, Vet Approved
ChlorpropamideThe metabolism of Chlorpropamide can be increased when combined with Phenytoin.Approved
ChlorprothixeneThe serum concentration of Phenytoin can be increased when it is combined with Chlorprothixene.Approved, Withdrawn
ChlorzoxazoneThe metabolism of Chlorzoxazone can be increased when combined with Phenytoin.Approved
CholecalciferolThe metabolism of Cholecalciferol can be increased when combined with Phenytoin.Approved, Nutraceutical
CholesterolThe serum concentration of Phenytoin can be increased when it is combined with Cholesterol.Experimental
Cholic AcidThe serum concentration of Phenytoin can be decreased when it is combined with Cholic Acid.Approved
CiclesonideThe metabolism of Ciclesonide can be increased when combined with Phenytoin.Approved, Investigational
CiclopiroxThe serum concentration of Phenytoin can be increased when it is combined with Ciclopirox.Approved, Investigational
CilazaprilThe serum concentration of Phenytoin can be increased when it is combined with Cilazapril.Approved
CilnidipineThe serum concentration of Phenytoin can be increased when it is combined with Cilnidipine.Approved
CilostazolThe metabolism of Cilostazol can be increased when combined with Phenytoin.Approved
CimetidineThe risk or severity of adverse effects can be increased when Cimetidine is combined with Phenytoin.Approved
CinacalcetThe metabolism of Cinacalcet can be increased when combined with Phenytoin.Approved
CinchocaineThe risk or severity of adverse effects can be increased when Cinchocaine is combined with Phenytoin.Approved, Vet Approved
CinnarizineThe serum concentration of Phenytoin can be increased when it is combined with Cinnarizine.Approved
CiprofloxacinThe therapeutic efficacy of Phenytoin can be decreased when used in combination with Ciprofloxacin.Approved, Investigational
CiprofloxacinThe serum concentration of Phenytoin can be increased when it is combined with Ciprofloxacin.Approved, Investigational
CisaprideThe metabolism of Cisapride can be increased when combined with Phenytoin.Approved, Investigational, Withdrawn
CisplatinThe serum concentration of Phenytoin can be decreased when it is combined with Cisplatin.Approved
CitalopramThe metabolism of Citalopram can be increased when combined with Phenytoin.Approved
ClarithromycinThe serum concentration of the active metabolites of Clarithromycin can be increased when Clarithromycin is used in combination with Phenytoin.Approved
ClemastineThe metabolism of Phenytoin can be decreased when combined with Clemastine.Approved
ClevidipineThe serum concentration of Phenytoin can be increased when it is combined with Clevidipine.Approved
ClidiniumThe risk or severity of adverse effects can be increased when Phenytoin is combined with Clidinium.Approved
ClindamycinThe metabolism of Clindamycin can be increased when combined with Phenytoin.Approved, Vet Approved
ClobazamThe metabolism of Clobazam can be increased when combined with Phenytoin.Approved, Illicit
ClobetasolThe serum concentration of Clobetasol can be decreased when it is combined with Phenytoin.Investigational
Clobetasol propionateThe serum concentration of Clobetasol propionate can be decreased when it is combined with Phenytoin.Approved
ClocortoloneThe serum concentration of Clocortolone can be decreased when it is combined with Phenytoin.Approved
ClofazimineThe metabolism of Clofazimine can be increased when combined with Phenytoin.Approved, Investigational
ClofibrateThe metabolism of Clofibrate can be increased when combined with Phenytoin.Approved
clomethiazoleThe metabolism of clomethiazole can be increased when combined with Phenytoin.Investigational
ClomipramineThe metabolism of Clomipramine can be increased when combined with Phenytoin.Approved, Vet Approved
ClonazepamThe serum concentration of Phenytoin can be increased when it is combined with Clonazepam.Approved, Illicit
ClonidineThe metabolism of Clonidine can be increased when combined with Phenytoin.Approved
ClopidogrelThe metabolism of Clopidogrel can be increased when combined with Phenytoin.Approved, Nutraceutical
ClorazepateThe serum concentration of Phenytoin can be increased when it is combined with Clorazepate.Approved, Illicit
ClotiazepamThe metabolism of Clotiazepam can be increased when combined with Phenytoin.Approved, Illicit
ClotrimazoleThe serum concentration of Phenytoin can be increased when it is combined with Clotrimazole.Approved, Vet Approved
ClozapineThe serum concentration of Clozapine can be decreased when it is combined with Phenytoin.Approved
CobicistatThe serum concentration of Cobicistat can be decreased when it is combined with Phenytoin.Approved
CobimetinibThe serum concentration of Cobimetinib can be decreased when it is combined with Phenytoin.Approved
CocaineThe metabolism of Cocaine can be increased when combined with Phenytoin.Approved, Illicit
CodeineThe metabolism of Codeine can be increased when combined with Phenytoin.Approved, Illicit
Coenzyme Q10The serum concentration of Coenzyme Q10 can be decreased when it is combined with Phenytoin.Experimental
ColchicineThe metabolism of Colchicine can be increased when combined with Phenytoin.Approved
ColesevelamThe serum concentration of Phenytoin can be decreased when it is combined with Colesevelam.Approved
ColforsinThe serum concentration of Phenytoin can be increased when it is combined with Colforsin.Experimental
ConivaptanThe serum concentration of Phenytoin can be increased when it is combined with Conivaptan.Approved, Investigational
Conjugated Equine EstrogensThe therapeutic efficacy of Conjugated Equine Estrogens can be decreased when used in combination with Phenytoin.Approved
CordycepinThe serum concentration of Phenytoin can be increased when it is combined with Cordycepin.Investigational
Cortisone acetateThe metabolism of Cortisone acetate can be increased when combined with Phenytoin.Approved
CrizotinibThe serum concentration of Crizotinib can be decreased when it is combined with Phenytoin.Approved
CyclizineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Cyclizine.Approved
CyclobenzaprineThe metabolism of Cyclobenzaprine can be increased when combined with Phenytoin.Approved
CyclophosphamideThe metabolism of Cyclophosphamide can be increased when combined with Phenytoin.Approved, Investigational
CyclosporineThe metabolism of Cyclosporine can be increased when combined with Phenytoin.Approved, Investigational, Vet Approved
CyclosporineThe serum concentration of Phenytoin can be increased when it is combined with Cyclosporine.Approved, Investigational, Vet Approved
CyproheptadineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Cyproheptadine.Approved
CytarabineThe metabolism of Cytarabine can be increased when combined with Phenytoin.Approved, Investigational
DabrafenibThe serum concentration of Phenytoin can be decreased when it is combined with Dabrafenib.Approved
DaclatasvirThe serum concentration of Daclatasvir can be decreased when it is combined with Phenytoin.Approved
DactinomycinThe serum concentration of Phenytoin can be increased when it is combined with Dactinomycin.Approved
DantroleneThe metabolism of Dantrolene can be increased when combined with Phenytoin.Approved
DapagliflozinThe metabolism of Dapagliflozin can be increased when combined with Phenytoin.Approved
DapiprazoleThe risk or severity of adverse effects can be increased when Dapiprazole is combined with Phenytoin.Approved
DapoxetineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Dapoxetine.Investigational
DapsoneThe metabolism of Dapsone can be increased when combined with Phenytoin.Approved, Investigational
DapsoneThe risk or severity of adverse effects can be increased when Dapsone is combined with Phenytoin.Approved, Investigational
DarifenacinThe metabolism of Darifenacin can be increased when combined with Phenytoin.Approved, Investigational
DarodipineThe serum concentration of Phenytoin can be increased when it is combined with Darodipine.Experimental
DarunavirThe serum concentration of Phenytoin can be decreased when it is combined with Darunavir.Approved
DasabuvirThe serum concentration of Dasabuvir can be decreased when it is combined with Phenytoin.Approved
DasatinibThe serum concentration of Dasatinib can be decreased when it is combined with Phenytoin.Approved, Investigational
DaunorubicinThe metabolism of Daunorubicin can be increased when combined with Phenytoin.Approved
Decanoic AcidThe serum concentration of Phenytoin can be increased when it is combined with Decanoic Acid.Experimental
DeferasiroxThe serum concentration of Deferasirox can be decreased when it is combined with Phenytoin.Approved, Investigational
dehydroepiandrosterone sulfateThe serum concentration of dehydroepiandrosterone sulfate can be decreased when it is combined with Phenytoin.Investigational
DelavirdineThe serum concentration of Delavirdine can be decreased when it is combined with Phenytoin.Approved
DelorazepamThe serum concentration of Phenytoin can be increased when it is combined with Delorazepam.Approved, Illicit
deramciclaneThe risk or severity of adverse effects can be increased when deramciclane is combined with Phenytoin.Investigational
DesfluraneThe risk or severity of adverse effects can be increased when Desflurane is combined with Phenytoin.Approved
DesipramineThe metabolism of Desipramine can be increased when combined with Phenytoin.Approved
DesloratadineThe serum concentration of Phenytoin can be increased when it is combined with Desloratadine.Approved, Investigational
DesogestrelThe therapeutic efficacy of Desogestrel can be decreased when used in combination with Phenytoin.Approved
DesoximetasoneThe serum concentration of Desoximetasone can be decreased when it is combined with Phenytoin.Approved
Desoxycorticosterone acetateThe serum concentration of Desoxycorticosterone acetate can be decreased when it is combined with Phenytoin.Approved
Desoxycorticosterone PivalateThe serum concentration of Desoxycorticosterone Pivalate can be decreased when it is combined with Phenytoin.Experimental, Vet Approved
DesvenlafaxineThe metabolism of Desvenlafaxine can be increased when combined with Phenytoin.Approved
DetomidineThe risk or severity of adverse effects can be increased when Detomidine is combined with Phenytoin.Vet Approved
DexamethasoneThe serum concentration of Dexamethasone can be decreased when it is combined with Phenytoin.Approved, Investigational, Vet Approved
DexamethasoneThe metabolism of Dexamethasone can be increased when combined with Phenytoin.Approved, Investigational, Vet Approved
Dexamethasone isonicotinateThe serum concentration of Dexamethasone isonicotinate can be decreased when it is combined with Phenytoin.Vet Approved
DexbrompheniramineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Dexbrompheniramine.Approved
DexketoprofenThe risk or severity of adverse effects can be increased when Dexketoprofen is combined with Phenytoin.Approved
DexmedetomidineThe risk or severity of adverse effects can be increased when Dexmedetomidine is combined with Phenytoin.Approved, Vet Approved
DexmethylphenidateThe serum concentration of Phenytoin can be increased when it is combined with Dexmethylphenidate.Approved
DextroamphetamineThe serum concentration of Phenytoin can be decreased when it is combined with Dextroamphetamine.Approved, Illicit
DextromethorphanThe metabolism of Dextromethorphan can be increased when combined with Phenytoin.Approved
DextromoramideThe risk or severity of adverse effects can be increased when Dextromoramide is combined with Phenytoin.Experimental, Illicit
DextropropoxypheneThe metabolism of Dextropropoxyphene can be increased when combined with Phenytoin.Approved, Illicit, Withdrawn
DezocineThe risk or severity of adverse effects can be increased when Dezocine is combined with Phenytoin.Approved
DiazepamThe serum concentration of Phenytoin can be increased when it is combined with Diazepam.Approved, Illicit, Vet Approved
DiazoxideThe serum concentration of Phenytoin can be decreased when it is combined with Diazoxide.Approved
DiclofenacThe metabolism of Diclofenac can be increased when combined with Phenytoin.Approved, Vet Approved
DiclofenacThe serum concentration of Diclofenac can be decreased when it is combined with Phenytoin.Approved, Vet Approved
DiclofenamideThe risk or severity of adverse effects can be increased when Diclofenamide is combined with Phenytoin.Approved
DicoumarolPhenytoin may increase the anticoagulant activities of Dicoumarol.Approved
DienestrolThe therapeutic efficacy of Dienestrol can be decreased when used in combination with Phenytoin.Approved
DienogestThe serum concentration of Dienogest can be decreased when it is combined with Phenytoin.Approved
DiethylpropionThe serum concentration of Phenytoin can be decreased when it is combined with Diethylpropion.Approved, Illicit
DiethylstilbestrolThe therapeutic efficacy of Diethylstilbestrol can be decreased when used in combination with Phenytoin.Approved
DifenoxinThe risk or severity of adverse effects can be increased when Phenytoin is combined with Difenoxin.Approved, Illicit
DiflorasoneThe serum concentration of Diflorasone can be decreased when it is combined with Phenytoin.Approved
DifluocortoloneThe serum concentration of Difluocortolone can be decreased when it is combined with Phenytoin.Approved
DifluprednateThe serum concentration of Difluprednate can be decreased when it is combined with Phenytoin.Approved
DigitoxinThe metabolism of Digitoxin can be increased when combined with Phenytoin.Approved
DigoxinThe metabolism of Digoxin can be increased when combined with Phenytoin.Approved
DihydrocodeineThe metabolism of Dihydrocodeine can be increased when combined with Phenytoin.Approved, Illicit
DihydroergotamineThe metabolism of Dihydroergotamine can be increased when combined with Phenytoin.Approved
DihydroetorphineThe risk or severity of adverse effects can be increased when Dihydroetorphine is combined with Phenytoin.Experimental, Illicit
DihydromorphineThe risk or severity of adverse effects can be increased when Dihydromorphine is combined with Phenytoin.Experimental, Illicit
DiltiazemThe serum concentration of Phenytoin can be increased when it is combined with Diltiazem.Approved
DimenhydrinateThe risk or severity of adverse effects can be increased when Phenytoin is combined with Dimenhydrinate.Approved
DiphenhydramineThe metabolism of Diphenhydramine can be increased when combined with Phenytoin.Approved
DiphenoxylateThe risk or severity of adverse effects can be increased when Diphenoxylate is combined with Phenytoin.Approved, Illicit
DipyridamoleThe serum concentration of Phenytoin can be increased when it is combined with Dipyridamole.Approved
DisopyramideThe serum concentration of Disopyramide can be decreased when it is combined with Phenytoin.Approved
DisulfiramThe serum concentration of Phenytoin can be increased when it is combined with Disulfiram.Approved
DocetaxelThe metabolism of Docetaxel can be increased when combined with Phenytoin.Approved, Investigational
DofetilideThe metabolism of Dofetilide can be increased when combined with Phenytoin.Approved
DolasetronThe metabolism of Dolasetron can be increased when combined with Phenytoin.Approved
DolutegravirThe serum concentration of Dolutegravir can be decreased when it is combined with Phenytoin.Approved
DomperidoneThe metabolism of Domperidone can be increased when combined with Phenytoin.Approved, Investigational, Vet Approved
DonepezilThe metabolism of Donepezil can be increased when combined with Phenytoin.Approved
DopamineThe metabolism of Dopamine can be increased when combined with Phenytoin.Approved
DoramectinThe risk or severity of adverse effects can be increased when Doramectin is combined with Phenytoin.Vet Approved
DorzolamideThe metabolism of Dorzolamide can be increased when combined with Phenytoin.Approved
DotarizineThe serum concentration of Phenytoin can be increased when it is combined with Dotarizine.Investigational
DoxazosinThe metabolism of Doxazosin can be increased when combined with Phenytoin.Approved
DoxepinThe metabolism of Doxepin can be increased when combined with Phenytoin.Approved
DoxofyllineThe serum concentration of Doxofylline can be decreased when it is combined with Phenytoin.Approved
DoxorubicinThe serum concentration of Doxorubicin can be decreased when it is combined with Phenytoin.Approved, Investigational
DoxorubicinThe metabolism of Doxorubicin can be increased when combined with Phenytoin.Approved, Investigational
DoxycyclineThe serum concentration of Doxycycline can be decreased when it is combined with Phenytoin.Approved, Investigational, Vet Approved
DoxylamineDoxylamine may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.Approved, Vet Approved
DPDPEThe risk or severity of adverse effects can be increased when DPDPE is combined with Phenytoin.Investigational
DronabinolDronabinol may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.Approved, Illicit
DronedaroneThe serum concentration of Dronedarone can be decreased when it is combined with Phenytoin.Approved
DroperidolDroperidol may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.Approved, Vet Approved
DrospirenoneThe therapeutic efficacy of Drospirenone can be decreased when used in combination with Phenytoin.Approved
DrotebanolThe risk or severity of adverse effects can be increased when Drotebanol is combined with Phenytoin.Experimental, Illicit
DuloxetineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Duloxetine.Approved
DutasterideThe metabolism of Dutasteride can be increased when combined with Phenytoin.Approved, Investigational
DyclonineThe risk or severity of adverse effects can be increased when Dyclonine is combined with Phenytoin.Approved
DyphyllineThe serum concentration of Dyphylline can be decreased when it is combined with Phenytoin.Approved
EcgonineThe risk or severity of adverse effects can be increased when Ecgonine is combined with Phenytoin.Experimental, Illicit
ECGONINE METHYL ESTERThe risk or severity of adverse effects can be increased when ECGONINE METHYL ESTER is combined with Phenytoin.Experimental
EconazoleThe serum concentration of Phenytoin can be increased when it is combined with Econazole.Approved
EcopipamThe risk or severity of adverse effects can be increased when Phenytoin is combined with Ecopipam.Investigational
EfavirenzThe serum concentration of Efavirenz can be decreased when it is combined with Phenytoin.Approved, Investigational
EfinaconazoleThe serum concentration of Phenytoin can be increased when it is combined with Efinaconazole.Approved
EfonidipineThe serum concentration of Phenytoin can be increased when it is combined with Efonidipine.Approved
ElbasvirThe serum concentration of Phenytoin can be increased when it is combined with Elbasvir.Approved
EletriptanThe metabolism of Eletriptan can be increased when combined with Phenytoin.Approved, Investigational
EliglustatThe serum concentration of Eliglustat can be decreased when it is combined with Phenytoin.Approved
EltrombopagThe metabolism of Eltrombopag can be increased when combined with Phenytoin.Approved
ElvitegravirThe serum concentration of Elvitegravir can be decreased when it is combined with Phenytoin.Approved
EnalaprilThe metabolism of Enalapril can be increased when combined with Phenytoin.Approved, Vet Approved
EnfluraneThe risk or severity of adverse effects can be increased when Enflurane is combined with Phenytoin.Approved, Vet Approved
EnfuvirtideThe metabolism of Enfuvirtide can be increased when combined with Phenytoin.Approved, Investigational
EntacaponeThe risk or severity of adverse effects can be increased when Phenytoin is combined with Entacapone.Approved, Investigational
EnzalutamideThe serum concentration of Enzalutamide can be decreased when it is combined with Phenytoin.Approved
EperisoneThe serum concentration of Phenytoin can be increased when it is combined with Eperisone.Approved, Investigational
EpinastineThe metabolism of Epinastine can be increased when combined with Phenytoin.Approved, Investigational
EplerenoneThe metabolism of Eplerenone can be increased when combined with Phenytoin.Approved
EpoprostenolThe metabolism of Epoprostenol can be increased when combined with Phenytoin.Approved
EquileninThe serum concentration of Equilenin can be decreased when it is combined with Phenytoin.Experimental
EquilinThe serum concentration of Equilin can be decreased when it is combined with Phenytoin.Approved
ErgocalciferolThe metabolism of Ergocalciferol can be increased when combined with Phenytoin.Approved, Nutraceutical
Ergoloid mesylateThe metabolism of Ergoloid mesylate can be increased when combined with Phenytoin.Approved
ErgonovineThe metabolism of Ergonovine can be increased when combined with Phenytoin.Approved
ErgotamineThe metabolism of Ergotamine can be increased when combined with Phenytoin.Approved
ErlotinibThe serum concentration of Erlotinib can be decreased when it is combined with Phenytoin.Approved, Investigational
ErythromycinThe metabolism of Erythromycin can be increased when combined with Phenytoin.Approved, Vet Approved
EscitalopramThe metabolism of Escitalopram can be increased when combined with Phenytoin.Approved, Investigational
Eslicarbazepine acetateThe serum concentration of Eslicarbazepine acetate can be decreased when it is combined with Phenytoin.Approved
EsomeprazoleThe metabolism of Esomeprazole can be increased when combined with Phenytoin.Approved, Investigational
EstazolamThe serum concentration of Phenytoin can be increased when it is combined with Estazolam.Approved, Illicit
EstradiolThe therapeutic efficacy of Estradiol can be decreased when used in combination with Phenytoin.Approved, Investigational, Vet Approved
Estradiol valerate/DienogestThe metabolism of Estradiol valerate/Dienogest can be increased when combined with Phenytoin.Approved
EstramustineThe therapeutic efficacy of Estramustine can be decreased when used in combination with Phenytoin.Approved
EstriolThe serum concentration of Phenytoin can be decreased when it is combined with Estriol.Approved, Vet Approved
Estrogens, esterifiedThe therapeutic efficacy of Estrogens, esterified can be decreased when used in combination with Phenytoin.Approved
EstroneThe metabolism of Estrone can be increased when combined with Phenytoin.Approved
Estrone sulfateThe therapeutic efficacy of Estrone sulfate can be decreased when used in combination with Phenytoin.Approved
EszopicloneThe metabolism of Eszopiclone can be increased when combined with Phenytoin.Approved
Etacrynic acidPhenytoin may decrease the diuretic activities of Etacrynic acid.Approved
EthanolEthanol may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.Approved
EthchlorvynolThe risk or severity of adverse effects can be increased when Ethchlorvynol is combined with Phenytoin.Approved, Illicit, Withdrawn
Ethinyl EstradiolThe therapeutic efficacy of Ethinyl Estradiol can be decreased when used in combination with Phenytoin.Approved
EthosuximideEthosuximide may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.Approved
EthotoinThe risk or severity of adverse effects can be increased when Phenytoin is combined with Ethotoin.Approved
EthoxzolamideThe risk or severity of adverse effects can be increased when Ethoxzolamide is combined with Phenytoin.Withdrawn
Ethyl biscoumacetatePhenytoin may increase the anticoagulant activities of Ethyl biscoumacetate.Withdrawn
Ethyl carbamateThe risk or severity of adverse effects can be increased when Ethyl carbamate is combined with Phenytoin.Withdrawn
Ethyl loflazepateThe risk or severity of adverse effects can be increased when Ethyl loflazepate is combined with Phenytoin.Approved, Illicit
EthylmorphineThe metabolism of Ethylmorphine can be increased when combined with Phenytoin.Approved, Illicit
Ethynodiol diacetateThe therapeutic efficacy of Ethynodiol diacetate can be decreased when used in combination with Phenytoin.Approved
EtidocaineThe risk or severity of adverse effects can be increased when Etidocaine is combined with Phenytoin.Approved
EtifoxineThe risk or severity of adverse effects can be increased when Etifoxine is combined with Phenytoin.Withdrawn
EtizolamThe serum concentration of Phenytoin can be increased when it is combined with Etizolam.Approved
EtodolacThe metabolism of Etodolac can be increased when combined with Phenytoin.Approved, Investigational, Vet Approved
EtomidateThe risk or severity of adverse effects can be increased when Etomidate is combined with Phenytoin.Approved
EtonogestrelThe therapeutic efficacy of Etonogestrel can be decreased when used in combination with Phenytoin.Approved, Investigational
EtoperidoneThe risk or severity of adverse effects can be increased when Phenytoin is combined with Etoperidone.Approved
EtoposideThe serum concentration of Etoposide can be decreased when it is combined with Phenytoin.Approved
EtoricoxibThe metabolism of Etoricoxib can be increased when combined with Phenytoin.Approved, Investigational
EtorphineThe risk or severity of adverse effects can be increased when Etorphine is combined with Phenytoin.Illicit, Vet Approved
EtravirineThe serum concentration of Etravirine can be decreased when it is combined with Phenytoin.Approved
EverolimusThe serum concentration of Everolimus can be decreased when it is combined with Phenytoin.Approved
ExemestaneThe serum concentration of Exemestane can be decreased when it is combined with Phenytoin.Approved, Investigational
EzogabineThe serum concentration of Ezogabine can be decreased when it is combined with Phenytoin.Approved
FamciclovirThe metabolism of Famciclovir can be increased when combined with Phenytoin.Approved
FamotidineThe metabolism of Famotidine can be increased when combined with Phenytoin.Approved
FelbamateThe serum concentration of Phenytoin can be increased when it is combined with Felbamate.Approved
FelodipineThe serum concentration of Phenytoin can be increased when it is combined with Felodipine.Approved, Investigational
FencamfamineThe risk or severity of adverse effects can be increased when Fencamfamine is combined with Phenytoin.Approved, Illicit, Withdrawn
FendilineThe serum concentration of Phenytoin can be increased when it is combined with Fendiline.Withdrawn
FenofibrateThe metabolism of Fenofibrate can be increased when combined with Phenytoin.Approved
FentanylThe serum concentration of Fentanyl can be decreased when it is combined with Phenytoin.Approved, Illicit, Investigational, Vet Approved
FesoterodineThe metabolism of Fesoterodine can be increased when combined with Phenytoin.Approved
FexofenadineThe serum concentration of Phenytoin can be increased when it is combined with Fexofenadine.Approved
FidaxomicinThe serum concentration of Phenytoin can be increased when it is combined with Fidaxomicin.Approved
FinasterideThe metabolism of Finasteride can be increased when combined with Phenytoin.Approved
FingolimodThe metabolism of Fingolimod can be increased when combined with Phenytoin.Approved, Investigational
FlibanserinThe serum concentration of Flibanserin can be decreased when it is combined with Phenytoin.Approved
FloxuridineThe serum concentration of Phenytoin can be increased when it is combined with Floxuridine.Approved
fluasteroneThe serum concentration of fluasterone can be decreased when it is combined with Phenytoin.Investigational
FluconazoleThe serum concentration of Phenytoin can be increased when it is combined with Fluconazole.Approved
FlucytosineThe serum concentration of Phenytoin can be increased when it is combined with Flucytosine.Approved
FludiazepamThe serum concentration of Phenytoin can be increased when it is combined with Fludiazepam.Approved, Illicit
FludrocortisoneThe serum concentration of Fludrocortisone can be decreased when it is combined with Phenytoin.Approved
FluindionePhenytoin may increase the anticoagulant activities of Fluindione.Investigational
FlumazenilThe serum concentration of Phenytoin can be increased when it is combined with Flumazenil.Approved
FlumethasoneThe serum concentration of Flumethasone can be decreased when it is combined with Phenytoin.Approved, Vet Approved
FlunarizineThe serum concentration of Flunarizine can be decreased when it is combined with Phenytoin.Approved
FlunisolideThe metabolism of Flunisolide can be increased when combined with Phenytoin.Approved, Investigational
FlunitrazepamThe serum concentration of Phenytoin can be increased when it is combined with Flunitrazepam.Approved, Illicit
Fluocinolone AcetonideThe serum concentration of Fluocinolone Acetonide can be decreased when it is combined with Phenytoin.Approved, Investigational, Vet Approved
FluocinonideThe serum concentration of Fluocinonide can be decreased when it is combined with Phenytoin.Approved, Investigational
FluocortoloneThe serum concentration of Fluocortolone can be decreased when it is combined with Phenytoin.Approved, Withdrawn
FluorometholoneThe metabolism of Fluorometholone can be increased when combined with Phenytoin.Approved
FluorouracilThe serum concentration of Phenytoin can be increased when it is combined with Fluorouracil.Approved
FluorouracilThe metabolism of Phenytoin can be decreased when combined with Fluorouracil.Approved
FluoxetineThe serum concentration of Phenytoin can be increased when it is combined with Fluoxetine.Approved, Vet Approved
FlupentixolThe serum concentration of Phenytoin can be increased when it is combined with Flupentixol.Approved, Withdrawn
FluphenazineThe serum concentration of Phenytoin can be increased when it is combined with Fluphenazine.Approved
FluprednideneThe serum concentration of Fluprednidene can be decreased when it is combined with Phenytoin.Approved, Withdrawn
FluprednisoloneThe serum concentration of Fluprednisolone can be decreased when it is combined with Phenytoin.Approved
FlurandrenolideThe serum concentration of Flurandrenolide can be decreased when it is combined with Phenytoin.Approved
FlurazepamThe serum concentration of Phenytoin can be increased when it is combined with Flurazepam.Approved, Illicit
FlurbiprofenThe metabolism of Flurbiprofen can be increased when combined with Phenytoin.Approved, Investigational
FluspirileneThe risk or severity of adverse effects can be increased when Fluspirilene is combined with Phenytoin.Approved
FlutamideThe metabolism of Flutamide can be increased when combined with Phenytoin.Approved
Fluticasone furoateThe metabolism of Fluticasone furoate can be increased when combined with Phenytoin.Approved
Fluticasone PropionateThe metabolism of Fluticasone Propionate can be increased when combined with Phenytoin.Approved
FluvastatinThe serum concentration of Fluvastatin can be decreased when it is combined with Phenytoin.Approved
FluvoxamineThe serum concentration of Phenytoin can be increased when it is combined with Fluvoxamine.Approved, Investigational
Folic AcidThe serum concentration of Phenytoin can be decreased when it is combined with Folic Acid.Approved, Nutraceutical, Vet Approved
FormestaneThe serum concentration of Formestane can be decreased when it is combined with Phenytoin.Approved, Investigational, Withdrawn
FormoterolThe metabolism of Formoterol can be increased when combined with Phenytoin.Approved, Investigational
FosamprenavirThe serum concentration of Phenytoin can be decreased when it is combined with Fosamprenavir.Approved
FosaprepitantThe serum concentration of Phenytoin can be increased when it is combined with Fosaprepitant.Approved
FosphenytoinThe metabolism of Phenytoin can be increased when combined with Fosphenytoin.Approved
FospropofolThe risk or severity of adverse effects can be increased when Fospropofol is combined with Phenytoin.Approved, Illicit
FulvestrantThe metabolism of Fulvestrant can be increased when combined with Phenytoin.Approved, Investigational
FurosemidePhenytoin may decrease the diuretic activities of Furosemide.Approved, Vet Approved
Fusidic AcidThe serum concentration of Phenytoin can be increased when it is combined with Fusidic Acid.Approved
GabapentinThe serum concentration of Phenytoin can be increased when it is combined with Gabapentin.Approved, Investigational
gabapentin enacarbilThe risk or severity of adverse effects can be increased when Phenytoin is combined with gabapentin enacarbil.Approved
GalantamineThe metabolism of Galantamine can be increased when combined with Phenytoin.Approved
GallopamilThe serum concentration of Phenytoin can be increased when it is combined with Gallopamil.Investigational
Gamma Hydroxybutyric AcidThe risk or severity of adverse effects can be increased when Gamma Hydroxybutyric Acid is combined with Phenytoin.Approved, Illicit
GavestinelThe metabolism of Gavestinel can be increased when combined with Phenytoin.Investigational
GefitinibThe serum concentration of Gefitinib can be decreased when it is combined with Phenytoin.Approved, Investigational
GemfibrozilThe metabolism of Gemfibrozil can be increased when combined with Phenytoin.Approved
GenisteinThe serum concentration of Phenytoin can be increased when it is combined with Genistein.Investigational
GepironeThe risk or severity of adverse effects can be increased when Phenytoin is combined with Gepirone.Investigational
GestodeneThe therapeutic efficacy of Gestodene can be decreased when used in combination with Phenytoin.Approved
GliclazideThe metabolism of Gliclazide can be increased when combined with Phenytoin.Approved
GlimepirideThe metabolism of Glimepiride can be increased when combined with Phenytoin.Approved
GlipizideThe metabolism of Glipizide can be increased when combined with Phenytoin.Approved
GlucosamineThe metabolism of Glucosamine can be increased when combined with Phenytoin.Approved
GlutethimideThe risk or severity of adverse effects can be increased when Glutethimide is combined with Phenytoin.Approved, Illicit
GlyburideThe metabolism of Glyburide can be increased when combined with Phenytoin.Approved
GlycerolThe serum concentration of Phenytoin can be increased when it is combined with Glycerol.Experimental
GlyphosateThe serum concentration of Phenytoin can be increased when it is combined with Glyphosate.Experimental
Gramicidin DThe serum concentration of Phenytoin can be increased when it is combined with Gramicidin D.Approved
GranisetronThe metabolism of Granisetron can be increased when combined with Phenytoin.Approved, Investigational
GrepafloxacinThe metabolism of Grepafloxacin can be increased when combined with Phenytoin.Withdrawn
GriseofulvinThe serum concentration of Phenytoin can be increased when it is combined with Griseofulvin.Approved, Vet Approved
GuanfacineThe serum concentration of Guanfacine can be decreased when it is combined with Phenytoin.Approved, Investigational
HalazepamThe risk or severity of adverse effects can be increased when Halazepam is combined with Phenytoin.Approved, Illicit, Withdrawn
HalofantrineThe metabolism of Halofantrine can be increased when combined with Phenytoin.Approved
HaloperidolThe metabolism of Haloperidol can be increased when combined with Phenytoin.Approved
HaloproginThe serum concentration of Phenytoin can be increased when it is combined with Haloprogin.Approved, Withdrawn
HalothaneThe serum concentration of Phenytoin can be increased when it is combined with Halothane.Approved, Vet Approved
HE3286The serum concentration of HE3286 can be decreased when it is combined with Phenytoin.Investigational
HeroinThe risk or severity of adverse effects can be increased when Heroin is combined with Phenytoin.Approved, Illicit
HexestrolThe therapeutic efficacy of Hexestrol can be decreased when used in combination with Phenytoin.Withdrawn
HexetidineThe serum concentration of Phenytoin can be increased when it is combined with Hexetidine.Approved
HexobarbitalThe metabolism of Hexobarbital can be increased when combined with Phenytoin.Approved
Histamine PhosphateThe metabolism of Histamine Phosphate can be increased when combined with Phenytoin.Approved
HyaluronidaseThe therapeutic efficacy of Phenytoin can be decreased when used in combination with Hyaluronidase.Approved, Investigational
HydrocodonePhenytoin may increase the central nervous system depressant (CNS depressant) activities of Hydrocodone.Approved, Illicit
HydrocortisoneThe metabolism of Hydrocortisone can be increased when combined with Phenytoin.Approved, Vet Approved
HydrocortisoneThe serum concentration of Hydrocortisone can be decreased when it is combined with Phenytoin.Approved, Vet Approved
HydromorphoneThe metabolism of Hydromorphone can be increased when combined with Phenytoin.Approved, Illicit
Hydroxyamphetamine hydrobromideThe serum concentration of Phenytoin can be decreased when it is combined with Hydroxyamphetamine hydrobromide.Approved
Hydroxyprogesterone caproateThe metabolism of Hydroxyprogesterone caproate can be increased when combined with Phenytoin.Approved
HydroxyzineHydroxyzine may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.Approved
IbrutinibThe serum concentration of Ibrutinib can be decreased when it is combined with Phenytoin.Approved
IbuprofenThe metabolism of Ibuprofen can be increased when combined with Phenytoin.Approved
IdarubicinThe metabolism of Idarubicin can be increased when combined with Phenytoin.Approved
IdelalisibThe serum concentration of Phenytoin can be increased when it is combined with Idelalisib.Approved
IfosfamideThe serum concentration of the active metabolites of Ifosfamide can be increased when Ifosfamide is used in combination with Phenytoin.Approved
IloperidoneThe metabolism of Iloperidone can be increased when combined with Phenytoin.Approved
ImatinibThe serum concentration of Imatinib can be decreased when it is combined with Phenytoin.Approved
ImipramineThe metabolism of Imipramine can be increased when combined with Phenytoin.Approved
ImiquimodThe metabolism of Imiquimod can be increased when combined with Phenytoin.Approved, Investigational
IndacaterolThe metabolism of Indacaterol can be increased when combined with Phenytoin.Approved
IndalpineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Indalpine.Investigational, Withdrawn
IndapamideThe metabolism of Indapamide can be increased when combined with Phenytoin.Approved
IndinavirThe metabolism of Indinavir can be increased when combined with Phenytoin.Approved
indisulamThe metabolism of indisulam can be increased when combined with Phenytoin.Investigational
IndomethacinThe metabolism of Indomethacin can be increased when combined with Phenytoin.Approved, Investigational
Ipratropium bromideThe metabolism of Ipratropium bromide can be increased when combined with Phenytoin.Approved
IrbesartanThe metabolism of Irbesartan can be increased when combined with Phenytoin.Approved, Investigational
IrinotecanThe serum concentration of the active metabolites of Irinotecan can be reduced when Irinotecan is used in combination with Phenytoin resulting in a loss in efficacy.Approved, Investigational
IsavuconazoniumThe serum concentration of the active metabolites of Isavuconazonium can be reduced when Isavuconazonium is used in combination with Phenytoin resulting in a loss in efficacy.Approved, Investigational
IsoconazoleThe serum concentration of Phenytoin can be increased when it is combined with Isoconazole.Approved
IsofluraneThe metabolism of Isoflurane can be increased when combined with Phenytoin.Approved, Vet Approved
IsoniazidThe serum concentration of Phenytoin can be increased when it is combined with Isoniazid.Approved
Isosorbide DinitrateThe metabolism of Isosorbide Dinitrate can be increased when combined with Phenytoin.Approved
Isosorbide MononitrateThe metabolism of Isosorbide Mononitrate can be increased when combined with Phenytoin.Approved
IsradipineThe serum concentration of Phenytoin can be increased when it is combined with Isradipine.Approved
IstaroximeThe serum concentration of Istaroxime can be decreased when it is combined with Phenytoin.Investigational
ItraconazoleThe serum concentration of Itraconazole can be decreased when it is combined with Phenytoin.Approved, Investigational
IvabradineThe serum concentration of Ivabradine can be decreased when it is combined with Phenytoin.Approved
IvacaftorThe serum concentration of Ivacaftor can be decreased when it is combined with Phenytoin.Approved
IvermectinThe metabolism of Ivermectin can be increased when combined with Phenytoin.Approved, Vet Approved
IxabepiloneThe serum concentration of Ixabepilone can be decreased when it is combined with Phenytoin.Approved, Investigational
IxazomibThe serum concentration of Ixazomib can be decreased when it is combined with Phenytoin.Approved
KetamineThe metabolism of Ketamine can be increased when combined with Phenytoin.Approved, Vet Approved
KetazolamThe metabolism of Ketazolam can be increased when combined with Phenytoin.Approved
KetobemidoneThe metabolism of Ketobemidone can be increased when combined with Phenytoin.Approved
KetoconazoleThe serum concentration of Phenytoin can be increased when it is combined with Ketoconazole.Approved, Investigational
KetoprofenThe metabolism of Ketoprofen can be increased when combined with Phenytoin.Approved, Vet Approved
LacidipineThe serum concentration of Phenytoin can be increased when it is combined with Lacidipine.Approved
LacosamideThe serum concentration of Lacosamide can be decreased when it is combined with Phenytoin.Approved
LamotrigineThe serum concentration of Lamotrigine can be decreased when it is combined with Phenytoin.Approved, Investigational
LansoprazoleThe metabolism of Lansoprazole can be increased when combined with Phenytoin.Approved, Investigational
LapatinibThe serum concentration of Lapatinib can be decreased when it is combined with Phenytoin.Approved, Investigational
LaquinimodThe metabolism of Laquinimod can be increased when combined with Phenytoin.Investigational
LeflunomideThe metabolism of Leflunomide can be increased when combined with Phenytoin.Approved, Investigational
LenvatinibThe metabolism of Lenvatinib can be increased when combined with Phenytoin.Approved
LercanidipineThe serum concentration of Phenytoin can be increased when it is combined with Lercanidipine.Approved, Investigational
LesinuradThe metabolism of Lesinurad can be increased when combined with Phenytoin.Approved
LetrozoleThe metabolism of Letrozole can be increased when combined with Phenytoin.Approved, Investigational
LeucovorinThe serum concentration of Phenytoin can be decreased when it is combined with Leucovorin.Approved
LevetiracetamThe risk or severity of adverse effects can be increased when Phenytoin is combined with Levetiracetam.Approved, Investigational
LevobupivacaineThe metabolism of Levobupivacaine can be increased when combined with Phenytoin.Approved
LevocabastineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Levocabastine.Approved
LevocetirizineThe metabolism of Levocetirizine can be increased when combined with Phenytoin.Approved
LevodopaThe therapeutic efficacy of Levodopa can be decreased when used in combination with Phenytoin.Approved
LevofloxacinThe serum concentration of Phenytoin can be increased when it is combined with Levofloxacin.Approved, Investigational
LevoleucovorinThe serum concentration of Phenytoin can be decreased when it is combined with Levoleucovorin.Approved
Levomefolic acidThe serum concentration of Phenytoin can be decreased when it is combined with Levomefolic acid.Approved
Levomethadyl AcetateThe metabolism of Levomethadyl Acetate can be increased when combined with Phenytoin.Approved
LevomilnacipranThe metabolism of Levomilnacipran can be increased when combined with Phenytoin.Approved
LevonorgestrelThe therapeutic efficacy of Levonorgestrel can be decreased when used in combination with Phenytoin.Approved, Investigational
LevorphanolThe risk or severity of adverse effects can be increased when Levorphanol is combined with Phenytoin.Approved
LevothyroxineThe serum concentration of Levothyroxine can be decreased when it is combined with Phenytoin.Approved
LicofeloneThe metabolism of Licofelone can be increased when combined with Phenytoin.Investigational
LidocaineThe metabolism of Lidocaine can be increased when combined with Phenytoin.Approved, Vet Approved
LinagliptinThe serum concentration of Linagliptin can be decreased when it is combined with Phenytoin.Approved
LiothyronineThe serum concentration of Liothyronine can be decreased when it is combined with Phenytoin.Approved, Vet Approved
LiotrixThe serum concentration of Liotrix can be decreased when it is combined with Phenytoin.Approved
LisdexamfetamineThe serum concentration of Phenytoin can be decreased when it is combined with Lisdexamfetamine.Approved, Investigational
LisinoprilThe serum concentration of Phenytoin can be increased when it is combined with Lisinopril.Approved, Investigational
LisurideThe metabolism of Lisuride can be increased when combined with Phenytoin.Approved
LithiumThe risk or severity of adverse effects can be increased when Phenytoin is combined with Lithium.Approved
LofentanilThe risk or severity of adverse effects can be increased when Lofentanil is combined with Phenytoin.Illicit
LomitapideThe metabolism of Lomitapide can be increased when combined with Phenytoin.Approved
LoperamideThe metabolism of Loperamide can be increased when combined with Phenytoin.Approved
LopinavirThe serum concentration of Lopinavir can be decreased when it is combined with Phenytoin.Approved
LoratadineThe metabolism of Loratadine can be increased when combined with Phenytoin.Approved
LorazepamThe serum concentration of Phenytoin can be increased when it is combined with Lorazepam.Approved
LorcaserinThe metabolism of Lorcaserin can be increased when combined with Phenytoin.Approved
LornoxicamThe metabolism of Lornoxicam can be increased when combined with Phenytoin.Approved
LosartanThe metabolism of Losartan can be increased when combined with Phenytoin.Approved
LovastatinThe serum concentration of Lovastatin can be decreased when it is combined with Phenytoin.Approved, Investigational
LoxapineThe risk or severity of adverse effects can be increased when Loxapine is combined with Phenytoin.Approved
Lu AA21004The risk or severity of adverse effects can be increased when Lu AA21004 is combined with Phenytoin.Investigational
LuliconazoleThe serum concentration of Phenytoin can be increased when it is combined with Luliconazole.Approved
LumacaftorThe serum concentration of Phenytoin can be increased when it is combined with Lumacaftor.Approved
LumefantrineThe serum concentration of Lumefantrine can be decreased when it is combined with Phenytoin.Approved
LumiracoxibThe metabolism of Lumiracoxib can be increased when combined with Phenytoin.Approved, Investigational
LurasidoneThe serum concentration of Lurasidone can be decreased when it is combined with Phenytoin.Approved
LynestrenolThe therapeutic efficacy of Lynestrenol can be decreased when used in combination with Phenytoin.Investigational
MacitentanThe serum concentration of Macitentan can be decreased when it is combined with Phenytoin.Approved
Magnesium SulfateThe serum concentration of Phenytoin can be increased when it is combined with Magnesium Sulfate.Approved, Vet Approved
MalathionThe metabolism of Malathion can be increased when combined with Phenytoin.Approved, Investigational
ManidipineThe serum concentration of Phenytoin can be increased when it is combined with Manidipine.Approved
MaprotilineThe serum concentration of Phenytoin can be increased when it is combined with Maprotiline.Approved
MaravirocThe serum concentration of Maraviroc can be decreased when it is combined with Phenytoin.Approved, Investigational
ME-609The serum concentration of ME-609 can be decreased when it is combined with Phenytoin.Investigational
MebendazoleThe serum concentration of Mebendazole can be decreased when it is combined with Phenytoin.Approved, Vet Approved
MeclizineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Meclizine.Approved
MedetomidineThe risk or severity of adverse effects can be increased when Medetomidine is combined with Phenytoin.Vet Approved
Medroxyprogesterone acetateThe therapeutic efficacy of Medroxyprogesterone acetate can be decreased when used in combination with Phenytoin.Approved, Investigational
MedrysoneThe serum concentration of Medrysone can be decreased when it is combined with Phenytoin.Approved
Mefenamic acidThe metabolism of Mefenamic acid can be increased when combined with Phenytoin.Approved
MefloquineThe therapeutic efficacy of Phenytoin can be decreased when used in combination with Mefloquine.Approved
Megestrol acetateThe serum concentration of Phenytoin can be increased when it is combined with Megestrol acetate.Approved, Vet Approved
MelatoninThe metabolism of Melatonin can be increased when combined with Phenytoin.Approved, Nutraceutical, Vet Approved
MelengestrolThe serum concentration of Melengestrol can be decreased when it is combined with Phenytoin.Vet Approved
MeloxicamThe metabolism of Meloxicam can be increased when combined with Phenytoin.Approved, Vet Approved
MelperoneThe risk or severity of adverse effects can be increased when Melperone is combined with Phenytoin.Approved
MephedroneThe serum concentration of Phenytoin can be decreased when it is combined with Mephedrone.Investigational
MephentermineThe serum concentration of Phenytoin can be decreased when it is combined with Mephentermine.Approved
MephenytoinThe metabolism of Mephenytoin can be increased when combined with Phenytoin.Investigational, Withdrawn
MepivacaineThe risk or severity of adverse effects can be increased when Mepivacaine is combined with Phenytoin.Approved, Vet Approved
MeprobamateThe metabolism of Meprobamate can be increased when combined with Phenytoin.Approved, Illicit
MesoridazineThe risk or severity of adverse effects can be increased when Mesoridazine is combined with Phenytoin.Approved
MestranolThe therapeutic efficacy of Mestranol can be decreased when used in combination with Phenytoin.Approved
MetaxaloneThe risk or severity of adverse effects can be increased when Phenytoin is combined with Metaxalone.Approved
MethadoneThe serum concentration of Methadone can be decreased when it is combined with Phenytoin.Approved
Methadyl AcetateThe risk or severity of adverse effects can be increased when Methadyl Acetate is combined with Phenytoin.Approved, Illicit
MethallenestrilThe therapeutic efficacy of Methallenestril can be decreased when used in combination with Phenytoin.Experimental
MethamphetamineThe serum concentration of Phenytoin can be decreased when it is combined with Methamphetamine.Approved, Illicit
MethapyrileneThe risk or severity of adverse effects can be increased when Methapyrilene is combined with Phenytoin.Withdrawn
MethaqualoneThe metabolism of Methaqualone can be increased when combined with Phenytoin.Illicit, Withdrawn
MethazolamideThe risk or severity of adverse effects can be increased when Methazolamide is combined with Phenytoin.Approved
MethocarbamolThe risk or severity of adverse effects can be increased when Phenytoin is combined with Methocarbamol.Approved, Vet Approved
MethohexitalThe risk or severity of adverse effects can be increased when Methohexital is combined with Phenytoin.Approved
MethotrexateThe serum concentration of Phenytoin can be decreased when it is combined with Methotrexate.Approved
MethotrimeprazinePhenytoin may increase the central nervous system depressant (CNS depressant) activities of Methotrimeprazine.Approved
MethoxsalenThe metabolism of Methoxsalen can be increased when combined with Phenytoin.Approved
MethoxyfluraneThe metabolism of Methoxyflurane can be increased when combined with Phenytoin.Approved, Vet Approved
MethsuximideThe metabolism of Methsuximide can be increased when combined with Phenytoin.Approved
MethylphenidateThe serum concentration of Phenytoin can be increased when it is combined with Methylphenidate.Approved, Investigational
MethylphenobarbitalThe metabolism of Methylphenobarbital can be increased when combined with Phenytoin.Approved
MethylprednisoloneThe serum concentration of Methylprednisolone can be decreased when it is combined with Phenytoin.Approved, Vet Approved
MethyltestosteroneThe metabolism of Methyltestosterone can be increased when combined with Phenytoin.Approved
MetoprololThe metabolism of Metoprolol can be increased when combined with Phenytoin.Approved, Investigational
MetronidazoleThe metabolism of Metronidazole can be increased when combined with Phenytoin.Approved
MetronidazoleThe serum concentration of Metronidazole can be decreased when it is combined with Phenytoin.Approved
MetyraponeThe serum concentration of Metyrapone can be decreased when it is combined with Phenytoin.Approved
MetyrosinePhenytoin may increase the sedative activities of Metyrosine.Approved
MevastatinThe serum concentration of Phenytoin can be increased when it is combined with Mevastatin.Experimental
MexiletineThe serum concentration of Mexiletine can be decreased when it is combined with Phenytoin.Approved
MianserinThe therapeutic efficacy of Phenytoin can be decreased when used in combination with Mianserin.Approved
MibefradilThe serum concentration of Phenytoin can be increased when it is combined with Mibefradil.Withdrawn
MicafunginThe serum concentration of Phenytoin can be increased when it is combined with Micafungin.Approved, Investigational
MiconazoleThe serum concentration of Phenytoin can be increased when it is combined with Miconazole.Approved, Investigational, Vet Approved
MidazolamThe serum concentration of Phenytoin can be increased when it is combined with Midazolam.Approved, Illicit
MifepristoneThe serum concentration of Mifepristone can be decreased when it is combined with Phenytoin.Approved, Investigational
MilnacipranThe risk or severity of adverse effects can be increased when Phenytoin is combined with Milnacipran.Approved
MiltefosineThe serum concentration of Phenytoin can be increased when it is combined with Miltefosine.Approved
MinocyclineMinocycline may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.Approved, Investigational
MirabegronThe metabolism of Mirabegron can be increased when combined with Phenytoin.Approved
MirtazapinePhenytoin may increase the central nervous system depressant (CNS depressant) activities of Mirtazapine.Approved
MitomycinThe serum concentration of Phenytoin can be increased when it is combined with Mitomycin.Approved
MitotaneThe serum concentration of Phenytoin can be decreased when it is combined with Mitotane.Approved
MitoxantroneThe serum concentration of Phenytoin can be decreased when it is combined with Mitoxantrone.Approved, Investigational
MivacuriumPhenytoin may decrease the neuromuscular blocking activities of Mivacurium.Approved
MMDAThe serum concentration of Phenytoin can be decreased when it is combined with MMDA.Experimental, Illicit
MoclobemideThe metabolism of Moclobemide can be increased when combined with Phenytoin.Approved
ModafinilThe metabolism of Modafinil can be increased when combined with Phenytoin.Approved, Investigational
MolindoneThe risk or severity of adverse effects can be increased when Molindone is combined with Phenytoin.Approved
MometasoneThe serum concentration of Mometasone can be decreased when it is combined with Phenytoin.Approved, Vet Approved
MonensinThe serum concentration of Phenytoin can be increased when it is combined with Monensin.Vet Approved
MontelukastThe metabolism of Montelukast can be increased when combined with Phenytoin.Approved
MorphineThe metabolism of Morphine can be increased when combined with Phenytoin.Approved, Investigational
muraglitazarThe metabolism of muraglitazar can be increased when combined with Phenytoin.Investigational
Mycophenolate mofetilThe metabolism of Mycophenolate mofetil can be increased when combined with Phenytoin.Approved, Investigational
MyxothiazolThe serum concentration of Phenytoin can be increased when it is combined with Myxothiazol.Experimental
NabiloneNabilone may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.Approved, Investigational
NafcillinThe serum concentration of Phenytoin can be decreased when it is combined with Nafcillin.Approved
NaftifineThe serum concentration of Phenytoin can be increased when it is combined with Naftifine.Approved
NaftopidilThe serum concentration of Phenytoin can be increased when it is combined with Naftopidil.Investigational
NalbuphineThe risk or severity of adverse effects can be increased when Nalbuphine is combined with Phenytoin.Approved
NaloxegolThe serum concentration of Naloxegol can be decreased when it is combined with Phenytoin.Approved
NaloxoneThe metabolism of Naloxone can be increased when combined with Phenytoin.Approved, Vet Approved
NaltrexoneThe serum concentration of Phenytoin can be increased when it is combined with Naltrexone.Approved, Investigational, Vet Approved
NaproxenThe metabolism of Naproxen can be increased when combined with Phenytoin.Approved, Vet Approved
NaringeninThe serum concentration of Phenytoin can be increased when it is combined with Naringenin.Experimental
NatamycinThe serum concentration of Phenytoin can be increased when it is combined with Natamycin.Approved
NateglinideThe metabolism of Nateglinide can be increased when combined with Phenytoin.Approved, Investigational
NCX 1022The serum concentration of NCX 1022 can be decreased when it is combined with Phenytoin.Investigational
NedaplatinThe serum concentration of Phenytoin can be decreased when it is combined with Nedaplatin.Approved
NefazodoneThe metabolism of Nefazodone can be increased when combined with Phenytoin.Approved, Withdrawn
NelfinavirThe serum concentration of Phenytoin can be decreased when it is combined with Nelfinavir.Approved
NeostigmineThe serum concentration of Phenytoin can be increased when it is combined with Neostigmine.Approved, Vet Approved
NetazepideThe serum concentration of Phenytoin can be increased when it is combined with Netazepide.Investigational
NetupitantThe serum concentration of Netupitant can be decreased when it is combined with Phenytoin.Approved
NevirapineThe metabolism of Phenytoin can be increased when combined with Nevirapine.Approved
NicardipineThe serum concentration of Phenytoin can be increased when it is combined with Nicardipine.Approved
NiclosamideThe metabolism of Niclosamide can be increased when combined with Phenytoin.Approved, Vet Approved
NicotineThe metabolism of Nicotine can be increased when combined with Phenytoin.Approved
NifedipineThe serum concentration of Phenytoin can be increased when it is combined with Nifedipine.Approved
NiguldipineThe serum concentration of Phenytoin can be increased when it is combined with Niguldipine.Experimental
NilotinibThe serum concentration of Nilotinib can be decreased when it is combined with Phenytoin.Approved, Investigational
NiludipineThe serum concentration of Phenytoin can be increased when it is combined with Niludipine.Experimental
NilutamideThe metabolism of Nilutamide can be increased when combined with Phenytoin.Approved
NilvadipineThe serum concentration of Phenytoin can be increased when it is combined with Nilvadipine.Approved
NimesulideThe serum concentration of Phenytoin can be increased when it is combined with Nimesulide.Approved, Withdrawn
NimodipineThe serum concentration of Nimodipine can be decreased when it is combined with Phenytoin.Approved
NisoldipineThe serum concentration of Nisoldipine can be decreased when it is combined with Phenytoin.Approved
NitrazepamThe serum concentration of Phenytoin can be increased when it is combined with Nitrazepam.Approved
NitrendipineThe serum concentration of Phenytoin can be increased when it is combined with Nitrendipine.Approved
Nitric OxideThe risk or severity of adverse effects can be increased when Nitric Oxide is combined with Phenytoin.Approved
Nitrous oxideThe risk or severity of adverse effects can be increased when Nitrous oxide is combined with Phenytoin.Approved, Vet Approved
NitroxolineThe serum concentration of Phenytoin can be increased when it is combined with Nitroxoline.Approved
NorelgestrominThe therapeutic efficacy of Norelgestromin can be decreased when used in combination with Phenytoin.Approved
NorethisteroneThe metabolism of Norethisterone can be increased when combined with Phenytoin.Approved
NorgestimateThe therapeutic efficacy of Norgestimate can be decreased when used in combination with Phenytoin.Approved
NorgestrelThe therapeutic efficacy of Norgestrel can be decreased when used in combination with Phenytoin.Approved
NormethadoneThe risk or severity of adverse effects can be increased when Normethadone is combined with Phenytoin.Approved, Illicit
NortriptylineThe metabolism of Nortriptyline can be increased when combined with Phenytoin.Approved
NOV-002The serum concentration of Phenytoin can be decreased when it is combined with NOV-002.Investigational
NystatinThe serum concentration of Phenytoin can be increased when it is combined with Nystatin.Approved, Vet Approved
OlanzapineThe risk or severity of adverse effects can be increased when Olanzapine is combined with Phenytoin.Approved, Investigational
OlaparibThe serum concentration of Olaparib can be decreased when it is combined with Phenytoin.Approved
Oleoyl estroneThe serum concentration of Oleoyl estrone can be decreased when it is combined with Phenytoin.Investigational
OlodaterolThe metabolism of Olodaterol can be increased when combined with Phenytoin.Approved
OlopatadineThe metabolism of Olopatadine can be increased when combined with Phenytoin.Approved
OmbitasvirThe serum concentration of Ombitasvir can be decreased when it is combined with Phenytoin.Approved
OmeprazoleThe serum concentration of Omeprazole can be decreased when it is combined with Phenytoin.Approved, Investigational, Vet Approved
OndansetronThe metabolism of Ondansetron can be increased when combined with Phenytoin.Approved
OpiumThe risk or severity of adverse effects can be increased when Opium is combined with Phenytoin.Approved, Illicit
OrlistatThe serum concentration of Phenytoin can be decreased when it is combined with Orlistat.Approved, Investigational
OrphenadrinePhenytoin may increase the central nervous system depressant (CNS depressant) activities of Orphenadrine.Approved
OsanetantThe risk or severity of adverse effects can be increased when Osanetant is combined with Phenytoin.Investigational
OsimertinibThe serum concentration of Osimertinib can be decreased when it is combined with Phenytoin.Approved
OspemifeneThe metabolism of Ospemifene can be increased when combined with Phenytoin.Approved
OxaliplatinThe serum concentration of Phenytoin can be decreased when it is combined with Oxaliplatin.Approved, Investigational
OxaprozinThe metabolism of Oxaprozin can be increased when combined with Phenytoin.Approved
OxazepamThe serum concentration of Phenytoin can be increased when it is combined with Oxazepam.Approved
OxcarbazepineThe serum concentration of the active metabolites of Oxcarbazepine can be reduced when Oxcarbazepine is used in combination with Phenytoin resulting in a loss in efficacy.Approved
OxetacaineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Oxetacaine.Investigational
OxiconazoleThe serum concentration of Phenytoin can be increased when it is combined with Oxiconazole.Approved
OxprenololThe risk or severity of adverse effects can be increased when Oxprenolol is combined with Phenytoin.Approved
OxybuprocaineThe risk or severity of adverse effects can be increased when Oxybuprocaine is combined with Phenytoin.Approved
OxybutyninThe metabolism of Oxybutynin can be increased when combined with Phenytoin.Approved, Investigational
OxycodoneThe metabolism of Oxycodone can be increased when combined with Phenytoin.Approved, Illicit, Investigational
OxymorphoneThe metabolism of Oxymorphone can be increased when combined with Phenytoin.Approved, Investigational, Vet Approved
P-NitrophenolThe serum concentration of Phenytoin can be increased when it is combined with P-Nitrophenol.Experimental
PaclitaxelThe metabolism of Paclitaxel can be increased when combined with Phenytoin.Approved, Vet Approved
pafuramidineThe serum concentration of Phenytoin can be increased when it is combined with pafuramidine.Investigational
PalbociclibThe serum concentration of Palbociclib can be decreased when it is combined with Phenytoin.Approved
PaliperidoneThe risk or severity of adverse effects can be increased when Paliperidone is combined with Phenytoin.Approved
Palmitic AcidThe serum concentration of Phenytoin can be increased when it is combined with Palmitic Acid.Experimental
PalonosetronThe metabolism of Palonosetron can be increased when combined with Phenytoin.Approved, Investigational
PanobinostatThe serum concentration of Panobinostat can be decreased when it is combined with Phenytoin.Approved, Investigational
PantoprazoleThe metabolism of Pantoprazole can be increased when combined with Phenytoin.Approved
ParaldehydePhenytoin may increase the central nervous system depressant (CNS depressant) activities of Paraldehyde.Approved
ParamethadioneThe metabolism of Paramethadione can be increased when combined with Phenytoin.Approved
ParamethasoneThe metabolism of Paramethasone can be increased when combined with Phenytoin.Approved
ParecoxibThe metabolism of Parecoxib can be increased when combined with Phenytoin.Approved
ParicalcitolThe metabolism of Paricalcitol can be increased when combined with Phenytoin.Approved, Investigational
ParitaprevirThe serum concentration of Paritaprevir can be decreased when it is combined with Phenytoin.Approved
ParoxetineThe serum concentration of Phenytoin can be increased when it is combined with Paroxetine.Approved, Investigational
PazopanibThe serum concentration of Pazopanib can be decreased when it is combined with Phenytoin.Approved
PentamidineThe serum concentration of Phenytoin can be increased when it is combined with Pentamidine.Approved
PentazocineThe risk or severity of adverse effects can be increased when Pentazocine is combined with Phenytoin.Approved, Vet Approved
PentobarbitalThe metabolism of Phenytoin can be increased when combined with Pentobarbital.Approved, Vet Approved
PerampanelThe serum concentration of Perampanel can be decreased when it is combined with Phenytoin.Approved
PerazineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Perazine.Investigational
PergolideThe metabolism of Pergolide can be increased when combined with Phenytoin.Approved, Vet Approved, Withdrawn
PerhexilineThe serum concentration of Phenytoin can be increased when it is combined with Perhexiline.Approved
PerindoprilThe serum concentration of Phenytoin can be increased when it is combined with Perindopril.Approved
PermethrinThe metabolism of Permethrin can be increased when combined with Phenytoin.Approved, Investigational
PerospironeThe risk or severity of adverse effects can be increased when Perospirone is combined with Phenytoin.Approved
PerphenazineThe metabolism of Perphenazine can be increased when combined with Phenytoin.Approved
PethidineThe serum concentration of Pethidine can be decreased when it is combined with Phenytoin.Approved
Pf 00477736The serum concentration of Phenytoin can be increased when it is combined with Pf 00477736.Investigational
PhenacetinThe metabolism of Phenacetin can be increased when combined with Phenytoin.Withdrawn
PhenindionePhenytoin may increase the anticoagulant activities of Phenindione.Approved
PhenobarbitalPhenytoin may increase the central nervous system depressant (CNS depressant) activities of Phenobarbital.Approved
PhenoxybenzamineThe metabolism of Phenoxybenzamine can be increased when combined with Phenytoin.Approved
PhenoxyethanolThe risk or severity of adverse effects can be increased when Phenoxyethanol is combined with Phenytoin.Approved
PhenprocoumonPhenytoin may increase the anticoagulant activities of Phenprocoumon.Approved
PhentermineThe serum concentration of Phenytoin can be decreased when it is combined with Phentermine.Approved, Illicit
PhenylbutazoneThe metabolism of Phenylbutazone can be increased when combined with Phenytoin.Approved, Vet Approved
PilocarpineThe metabolism of Pilocarpine can be increased when combined with Phenytoin.Approved
PimecrolimusThe metabolism of Pimecrolimus can be increased when combined with Phenytoin.Approved, Investigational
PimozideThe metabolism of Pimozide can be increased when combined with Phenytoin.Approved
PinacidilThe metabolism of Pinacidil can be increased when combined with Phenytoin.Withdrawn
PinaveriumThe serum concentration of Phenytoin can be increased when it is combined with Pinaverium.Approved
PioglitazoneThe metabolism of Pioglitazone can be increased when combined with Phenytoin.Approved, Investigational
PipamperoneThe risk or severity of adverse effects can be increased when Pipamperone is combined with Phenytoin.Approved
PipotiazineThe metabolism of Pipotiazine can be increased when combined with Phenytoin.Approved
PirenzepineThe serum concentration of Phenytoin can be increased when it is combined with Pirenzepine.Approved
PiretanidePhenytoin may decrease the diuretic activities of Piretanide.Experimental
PiritramideThe risk or severity of adverse effects can be increased when Phenytoin is combined with Piritramide.Investigational
PiroxicamThe metabolism of Piroxicam can be increased when combined with Phenytoin.Approved, Investigational
PitavastatinThe serum concentration of Pitavastatin can be decreased when it is combined with Phenytoin.Approved
PizotifenThe risk or severity of adverse effects can be increased when Phenytoin is combined with Pizotifen.Approved
Platelet Activating FactorThe serum concentration of Phenytoin can be decreased when it is combined with Platelet Activating Factor.Experimental
PodofiloxThe metabolism of Podofilox can be increased when combined with Phenytoin.Approved
PomalidomideThe metabolism of Pomalidomide can be increased when combined with Phenytoin.Approved
PonatinibThe serum concentration of Ponatinib can be decreased when it is combined with Phenytoin.Approved
PosaconazoleThe serum concentration of Phenytoin can be increased when it is combined with Posaconazole.Approved, Investigational, Vet Approved
PramipexolePhenytoin may increase the sedative activities of Pramipexole.Approved, Investigational
PramocaineThe risk or severity of adverse effects can be increased when Pramocaine is combined with Phenytoin.Approved
PrasteroneThe metabolism of Prasterone can be increased when combined with Phenytoin.Approved, Nutraceutical
PrasugrelThe metabolism of Prasugrel can be increased when combined with Phenytoin.Approved
PravastatinThe serum concentration of Pravastatin can be decreased when it is combined with Phenytoin.Approved
PrazepamThe serum concentration of Phenytoin can be increased when it is combined with Prazepam.Approved, Illicit
PraziquantelThe serum concentration of Praziquantel can be decreased when it is combined with Phenytoin.Approved, Vet Approved
PrazosinThe serum concentration of Phenytoin can be increased when it is combined with Prazosin.Approved
PrednicarbateThe serum concentration of Prednicarbate can be decreased when it is combined with Phenytoin.Approved
PrednisoloneThe metabolism of Prednisolone can be increased when combined with Phenytoin.Approved, Vet Approved
PrednisoloneThe serum concentration of Prednisolone can be decreased when it is combined with Phenytoin.Approved, Vet Approved
PrednisoneThe serum concentration of Prednisone can be decreased when it is combined with Phenytoin.Approved, Vet Approved
PregabalinThe serum concentration of Phenytoin can be increased when it is combined with Pregabalin.Approved, Illicit, Investigational
PregnanoloneThe risk or severity of adverse effects can be increased when Phenytoin is combined with Pregnanolone.Investigational
PregnenoloneThe serum concentration of Pregnenolone can be decreased when it is combined with Phenytoin.Experimental
PrenylamineThe serum concentration of Phenytoin can be increased when it is combined with Prenylamine.Withdrawn
PrilocaineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Prilocaine.Approved
PrimaquineThe metabolism of Primaquine can be increased when combined with Phenytoin.Approved
PrimidoneThe metabolism of Primidone can be increased when combined with Phenytoin.Approved, Vet Approved
ProbenecidThe serum concentration of Phenytoin can be increased when it is combined with Probenecid.Approved
ProcaineThe risk or severity of adverse effects can be increased when Procaine is combined with Phenytoin.Approved, Investigational, Vet Approved
ProchlorperazineThe metabolism of Prochlorperazine can be increased when combined with Phenytoin.Approved, Vet Approved
ProgesteroneThe metabolism of Progesterone can be increased when combined with Phenytoin.Approved, Vet Approved
ProguanilThe metabolism of Proguanil can be increased when combined with Phenytoin.Approved
PromazineThe metabolism of Promazine can be increased when combined with Phenytoin.Approved, Vet Approved
PromethazineThe metabolism of Promethazine can be increased when combined with Phenytoin.Approved
PropacetamolThe serum concentration of the active metabolites of Propacetamol can be reduced when Propacetamol is used in combination with Phenytoin resulting in a loss in efficacy.Approved
PropafenoneThe serum concentration of Propafenone can be decreased when it is combined with Phenytoin.Approved
ProparacaineThe risk or severity of adverse effects can be increased when Proparacaine is combined with Phenytoin.Approved, Vet Approved
PropofolThe metabolism of Propofol can be increased when combined with Phenytoin.Approved, Investigational, Vet Approved
PropoxycaineThe risk or severity of adverse effects can be increased when Propoxycaine is combined with Phenytoin.Approved
PropranololThe metabolism of Propranolol can be increased when combined with Phenytoin.Approved, Investigational
ProtriptylineThe serum concentration of Phenytoin can be increased when it is combined with Protriptyline.Approved
PSD502The risk or severity of adverse effects can be increased when PSD502 is combined with Phenytoin.Investigational
PseudoephedrineThe serum concentration of Phenytoin can be decreased when it is combined with Pseudoephedrine.Approved
PyrazinamideThe metabolism of Pyrazinamide can be increased when combined with Phenytoin.Approved
PyridoxineThe metabolism of Phenytoin can be increased when combined with Pyridoxine.Approved, Nutraceutical, Vet Approved
PyrimethamineThe metabolism of Phenytoin can be decreased when combined with Pyrimethamine.Approved, Vet Approved
QuazepamThe metabolism of Quazepam can be increased when combined with Phenytoin.Approved, Illicit
QuercetinThe serum concentration of Phenytoin can be increased when it is combined with Quercetin.Experimental
QuetiapineThe serum concentration of Quetiapine can be decreased when it is combined with Phenytoin.Approved
QuinacrineThe metabolism of Quinacrine can be increased when combined with Phenytoin.Approved
QuinidineThe serum concentration of Quinidine can be decreased when it is combined with Phenytoin.Approved
QuinineThe serum concentration of Quinine can be decreased when it is combined with Phenytoin.Approved
RabeprazoleThe metabolism of Rabeprazole can be increased when combined with Phenytoin.Approved, Investigational
RacloprideThe risk or severity of adverse effects can be increased when Phenytoin is combined with Raclopride.Investigational
RadicicolThe serum concentration of Phenytoin can be increased when it is combined with Radicicol.Experimental
RaloxifeneThe metabolism of Raloxifene can be increased when combined with Phenytoin.Approved, Investigational
RamelteonThe metabolism of Ramelteon can be increased when combined with Phenytoin.Approved, Investigational
RanitidineThe metabolism of Ranitidine can be increased when combined with Phenytoin.Approved
RanolazineThe serum concentration of Ranolazine can be decreased when it is combined with Phenytoin.Approved, Investigational
RapacuroniumPhenytoin may decrease the neuromuscular blocking activities of Rapacuronium.Withdrawn
ReboxetineThe metabolism of Reboxetine can be increased when combined with Phenytoin.Approved, Investigational
RegorafenibThe serum concentration of Regorafenib can be decreased when it is combined with Phenytoin.Approved
RemifentanilThe risk or severity of adverse effects can be increased when Remifentanil is combined with Phenytoin.Approved
RemoxiprideThe risk or severity of adverse effects can be increased when Remoxipride is combined with Phenytoin.Approved, Withdrawn
RepaglinideThe metabolism of Repaglinide can be increased when combined with Phenytoin.Approved, Investigational
ReserpineThe serum concentration of Phenytoin can be decreased when it is combined with Reserpine.Approved
RetapamulinThe metabolism of Retapamulin can be increased when combined with Phenytoin.Approved
RifabutinThe metabolism of Rifabutin can be increased when combined with Phenytoin.Approved
RifampicinThe serum concentration of Phenytoin can be decreased when it is combined with Rifampicin.Approved
RifapentineThe metabolism of Phenytoin can be increased when combined with Rifapentine.Approved
RilpivirineThe serum concentration of Rilpivirine can be decreased when it is combined with Phenytoin.Approved
RimexoloneThe serum concentration of Rimexolone can be decreased when it is combined with Phenytoin.Approved
RimonabantThe metabolism of Rimonabant can be increased when combined with Phenytoin.Approved, Investigational
RiociguatThe metabolism of Riociguat can be increased when combined with Phenytoin.Approved
RisedronateThe serum concentration of Phenytoin can be increased when it is combined with Risedronate.Approved, Investigational
RisperidoneThe metabolism of Risperidone can be increased when combined with Phenytoin.Approved, Investigational
RitanserinThe risk or severity of adverse effects can be increased when Phenytoin is combined with Ritanserin.Investigational
RitobegronThe serum concentration of Phenytoin can be decreased when it is combined with Ritobegron.Investigational
RitonavirThe serum concentration of Ritonavir can be decreased when it is combined with Phenytoin.Approved, Investigational
RivaroxabanThe serum concentration of Rivaroxaban can be decreased when it is combined with Phenytoin.Approved
RofecoxibThe metabolism of Rofecoxib can be increased when combined with Phenytoin.Investigational, Withdrawn
RoflumilastThe serum concentration of Roflumilast can be decreased when it is combined with Phenytoin.Approved
RolapitantThe serum concentration of Rolapitant can be decreased when it is combined with Phenytoin.Approved
RomidepsinThe serum concentration of Romidepsin can be decreased when it is combined with Phenytoin.Approved, Investigational
RomifidineThe risk or severity of adverse effects can be increased when Romifidine is combined with Phenytoin.Vet Approved
RopinirolePhenytoin may increase the sedative activities of Ropinirole.Approved, Investigational
RopivacaineThe metabolism of Ropivacaine can be increased when combined with Phenytoin.Approved
RosiglitazoneThe metabolism of Rosiglitazone can be increased when combined with Phenytoin.Approved, Investigational
RosuvastatinThe serum concentration of Rosuvastatin can be decreased when it is combined with Phenytoin.Approved
RotigotinePhenytoin may increase the sedative activities of Rotigotine.Approved
RoxithromycinThe metabolism of Roxithromycin can be increased when combined with Phenytoin.Approved, Withdrawn
RufinamideThe serum concentration of Phenytoin can be increased when it is combined with Rufinamide.Approved
RuxolitinibThe metabolism of Ruxolitinib can be increased when combined with Phenytoin.Approved
S-EthylisothioureaThe risk or severity of adverse effects can be increased when S-Ethylisothiourea is combined with Phenytoin.Experimental
Sage 547The risk or severity of adverse effects can be increased when Phenytoin is combined with Sage 547.Investigational
Salicylhydroxamic AcidThe serum concentration of Phenytoin can be increased when it is combined with Salicylhydroxamic Acid.Experimental
Salicylic acidThe serum concentration of Phenytoin can be increased when it is combined with Salicylic acid.Approved, Vet Approved
SalmeterolThe metabolism of Salmeterol can be increased when combined with Phenytoin.Approved
SaquinavirThe metabolism of Saquinavir can be increased when combined with Phenytoin.Approved, Investigational
SatraplatinThe serum concentration of Phenytoin can be decreased when it is combined with Satraplatin.Investigational
SaxagliptinThe serum concentration of Saxagliptin can be decreased when it is combined with Phenytoin.Approved
ScopolamineThe serum concentration of Phenytoin can be increased when it is combined with Scopolamine.Approved
SecobarbitalThe metabolism of Phenytoin can be increased when combined with Secobarbital.Approved, Vet Approved
SelegilineThe metabolism of Selegiline can be increased when combined with Phenytoin.Approved, Investigational, Vet Approved
SelexipagThe metabolism of Selexipag can be increased when combined with Phenytoin.Approved
SeratrodastThe metabolism of Seratrodast can be increased when combined with Phenytoin.Approved, Investigational
SertaconazoleThe serum concentration of Phenytoin can be increased when it is combined with Sertaconazole.Approved
SertindoleThe metabolism of Sertindole can be increased when combined with Phenytoin.Approved, Withdrawn
SertralineThe serum concentration of Phenytoin can be increased when it is combined with Sertraline.Approved
SevofluraneThe metabolism of Sevoflurane can be increased when combined with Phenytoin.Approved, Vet Approved
SibutramineThe metabolism of Sibutramine can be increased when combined with Phenytoin.Approved, Illicit, Investigational, Withdrawn
SildenafilThe metabolism of Sildenafil can be increased when combined with Phenytoin.Approved, Investigational
SilodosinThe metabolism of Silodosin can be increased when combined with Phenytoin.Approved
SiltuximabThe serum concentration of Phenytoin can be decreased when it is combined with Siltuximab.Approved
SimeprevirThe serum concentration of Simeprevir can be decreased when it is combined with Phenytoin.Approved
SimvastatinThe serum concentration of Simvastatin can be decreased when it is combined with Phenytoin.Approved
SinefunginThe serum concentration of Phenytoin can be increased when it is combined with Sinefungin.Experimental
SirolimusThe serum concentration of Sirolimus can be decreased when it is combined with Phenytoin.Approved, Investigational
SitagliptinThe metabolism of Sitagliptin can be increased when combined with Phenytoin.Approved, Investigational
SitaxentanThe metabolism of Sitaxentan can be increased when combined with Phenytoin.Approved, Investigational, Withdrawn
Sodium NitriteThe risk or severity of adverse effects can be increased when Phenytoin is combined with Sodium Nitrite.Approved
Sodium oxybateSodium oxybate may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.Approved
SolifenacinThe metabolism of Solifenacin can be increased when combined with Phenytoin.Approved
SonidegibThe serum concentration of Sonidegib can be decreased when it is combined with Phenytoin.Approved, Investigational
SorafenibThe serum concentration of Sorafenib can be decreased when it is combined with Phenytoin.Approved, Investigational
SpiramycinThe metabolism of Spiramycin can be increased when combined with Phenytoin.Approved
SpironolactoneThe serum concentration of Phenytoin can be increased when it is combined with Spironolactone.Approved
St. John's WortThe serum concentration of Phenytoin can be decreased when it is combined with St. John's Wort.Nutraceutical
StaurosporineThe serum concentration of Phenytoin can be increased when it is combined with Staurosporine.Experimental
StiripentolThe serum concentration of Phenytoin can be decreased when it is combined with Stiripentol.Approved
StreptozocinThe serum concentration of Phenytoin can be decreased when it is combined with Streptozocin.Approved
SufentanilThe metabolism of Sufentanil can be increased when combined with Phenytoin.Approved, Investigational
SulconazoleThe serum concentration of Phenytoin can be increased when it is combined with Sulconazole.Approved
SulfadiazineThe metabolism of Sulfadiazine can be increased when combined with Phenytoin.Approved, Vet Approved
SulfamethoxazoleThe serum concentration of Phenytoin can be increased when it is combined with Sulfamethoxazole.Approved
SulfamoxoleThe metabolism of Sulfamoxole can be increased when combined with Phenytoin.Approved
SulfinpyrazoneThe metabolism of Sulfinpyrazone can be increased when combined with Phenytoin.Approved
SulfisoxazoleThe metabolism of Sulfisoxazole can be increased when combined with Phenytoin.Approved, Vet Approved
SulpirideThe risk or severity of adverse effects can be increased when Sulpiride is combined with Phenytoin.Approved
SumatriptanThe serum concentration of Phenytoin can be increased when it is combined with Sumatriptan.Approved, Investigational
SunitinibThe serum concentration of Sunitinib can be decreased when it is combined with Phenytoin.Approved, Investigational
SuprofenThe metabolism of Suprofen can be increased when combined with Phenytoin.Approved, Withdrawn
SuvorexantThe serum concentration of Suvorexant can be decreased when it is combined with Phenytoin.Approved
Synthetic Conjugated Estrogens, AThe therapeutic efficacy of Synthetic Conjugated Estrogens, A can be decreased when used in combination with Phenytoin.Approved
Synthetic Conjugated Estrogens, BThe metabolism of Synthetic Conjugated Estrogens, B can be increased when combined with Phenytoin.Approved
TacrineThe serum concentration of Phenytoin can be increased when it is combined with Tacrine.Withdrawn
TacrolimusThe metabolism of Tacrolimus can be increased when combined with Phenytoin.Approved, Investigational
TacrolimusThe serum concentration of Tacrolimus can be decreased when it is combined with Phenytoin.Approved, Investigational
TadalafilThe serum concentration of Tadalafil can be decreased when it is combined with Phenytoin.Approved, Investigational
TamoxifenThe metabolism of Tamoxifen can be increased when combined with Phenytoin.Approved
TamsulosinThe metabolism of Tamsulosin can be increased when combined with Phenytoin.Approved, Investigational
TandospironeThe risk or severity of adverse effects can be increased when Phenytoin is combined with Tandospirone.Investigational
TapentadolTapentadol may increase the central nervous system depressant (CNS depressant) activities of Phenytoin.Approved
TasimelteonThe serum concentration of Tasimelteon can be decreased when it is combined with Phenytoin.Approved
TasosartanThe metabolism of Tasosartan can be increased when combined with Phenytoin.Approved
Taurochenodeoxycholic acidThe metabolism of Taurochenodeoxycholic acid can be increased when combined with Phenytoin.Experimental
Taurocholic AcidThe serum concentration of Phenytoin can be increased when it is combined with Taurocholic Acid.Experimental
TavaboroleThe serum concentration of Phenytoin can be increased when it is combined with Tavaborole.Approved
TazaroteneThe metabolism of Tazarotene can be increased when combined with Phenytoin.Approved, Investigational
TegafurThe serum concentration of Phenytoin can be increased when it is combined with Tegafur.Approved
TelaprevirThe serum concentration of Phenytoin can be increased when it is combined with Telaprevir.Approved
TelithromycinThe metabolism of Telithromycin can be increased when combined with Phenytoin.Approved
TelmisartanThe serum concentration of Phenytoin can be increased when it is combined with Telmisartan.Approved, Investigational
TemazepamThe serum concentration of Phenytoin can be increased when it is combined with Temazepam.Approved
TemsirolimusThe serum concentration of Temsirolimus can be decreased when it is combined with Phenytoin.Approved
TeniposideThe serum concentration of Teniposide can be decreased when it is combined with Phenytoin.Approved
TenoxicamThe metabolism of Tenoxicam can be increased when combined with Phenytoin.Approved
TerazosinThe serum concentration of Phenytoin can be increased when it is combined with Terazosin.Approved
TerbinafineThe serum concentration of Phenytoin can be increased when it is combined with Terbinafine.Approved, Investigational, Vet Approved
TerconazoleThe serum concentration of Phenytoin can be increased when it is combined with Terconazole.Approved
TerfenadineThe metabolism of Terfenadine can be increased when combined with Phenytoin.Withdrawn
TeriflunomideThe metabolism of Phenytoin can be decreased when combined with Teriflunomide.Approved
TesmilifeneThe metabolism of Tesmilifene can be increased when combined with Phenytoin.Investigational
TestosteroneThe metabolism of Testosterone can be increased when combined with Phenytoin.Approved, Investigational
TetrabenazineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Tetrabenazine.Approved
TetracaineThe risk or severity of adverse effects can be increased when Tetracaine is combined with Phenytoin.Approved, Vet Approved
TetracosactideTetracosactide may increase the hepatotoxic activities of Phenytoin.Approved
TetracyclineThe metabolism of Tetracycline can be increased when combined with Phenytoin.Approved, Vet Approved
TetrodotoxinThe risk or severity of adverse effects can be increased when Tetrodotoxin is combined with Phenytoin.Investigational
ThalidomidePhenytoin may increase the central nervous system depressant (CNS depressant) activities of Thalidomide.Approved, Investigational, Withdrawn
TheophyllineThe serum concentration of Theophylline can be decreased when it is combined with Phenytoin.Approved
ThiamylalThe metabolism of Thiamylal can be increased when combined with Phenytoin.Approved, Vet Approved
ThiopentalThe risk or severity of adverse effects can be increased when Thiopental is combined with Phenytoin.Approved, Vet Approved
ThioridazineThe metabolism of Thioridazine can be increased when combined with Phenytoin.Approved
ThiotepaThe metabolism of Thiotepa can be increased when combined with Phenytoin.Approved
ThiothixeneThe risk or severity of adverse effects can be increased when Thiothixene is combined with Phenytoin.Approved
ThymolThe serum concentration of Phenytoin can be increased when it is combined with Thymol.Approved
Thyroid, porcineThe serum concentration of Thyroid, porcine can be decreased when it is combined with Phenytoin.Approved
TiagabineThe metabolism of Tiagabine can be increased when combined with Phenytoin.Approved
TiaprideThe risk or severity of adverse effects can be increased when Phenytoin is combined with Tiapride.Investigational
TicagrelorThe serum concentration of the active metabolites of Ticagrelor can be reduced when Ticagrelor is used in combination with Phenytoin resulting in a loss in efficacy.Approved
TiclopidineThe serum concentration of Phenytoin can be increased when it is combined with Ticlopidine.Approved
TiletamineThe risk or severity of adverse effects can be increased when Tiletamine is combined with Phenytoin.Vet Approved
TimololThe metabolism of Timolol can be increased when combined with Phenytoin.Approved
TinidazoleThe metabolism of Tinidazole can be increased when combined with Phenytoin.Approved, Investigational
TioconazoleThe serum concentration of Phenytoin can be increased when it is combined with Tioconazole.Approved
TiotropiumThe metabolism of Tiotropium can be increased when combined with Phenytoin.Approved
TipranavirThe serum concentration of Tipranavir can be decreased when it is combined with Phenytoin.Approved, Investigational
TixocortolThe serum concentration of Tixocortol can be decreased when it is combined with Phenytoin.Approved
TizanidineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Tizanidine.Approved
TocilizumabThe serum concentration of Phenytoin can be decreased when it is combined with Tocilizumab.Approved
TofacitinibThe serum concentration of Tofacitinib can be decreased when it is combined with Phenytoin.Approved, Investigational
TolbutamideThe metabolism of Tolbutamide can be increased when combined with Phenytoin.Approved
TolcaponeThe risk or severity of adverse effects can be increased when Phenytoin is combined with Tolcapone.Approved, Withdrawn
Tolfenamic AcidThe serum concentration of Phenytoin can be increased when it is combined with Tolfenamic Acid.Approved
TolnaftateThe serum concentration of Phenytoin can be increased when it is combined with Tolnaftate.Approved, Vet Approved
TolterodineThe metabolism of Tolterodine can be increased when combined with Phenytoin.Approved, Investigational
TolvaptanThe serum concentration of Tolvaptan can be decreased when it is combined with Phenytoin.Approved
TopiramateThe serum concentration of Phenytoin can be increased when it is combined with Topiramate.Approved
TopotecanThe serum concentration of Topotecan can be decreased when it is combined with Phenytoin.Approved, Investigational
TorasemidePhenytoin may decrease the diuretic activities of Torasemide.Approved
ToremifeneThe serum concentration of Toremifene can be decreased when it is combined with Phenytoin.Approved, Investigational
TrabectedinThe serum concentration of Trabectedin can be decreased when it is combined with Phenytoin.Approved, Investigational
TramadolThe metabolism of Tramadol can be increased when combined with Phenytoin.Approved, Investigational
TranilastThe serum concentration of Phenytoin can be increased when it is combined with Tranilast.Approved, Investigational
Trans-2-PhenylcyclopropylamineThe risk or severity of adverse effects can be increased when Trans-2-Phenylcyclopropylamine is combined with Phenytoin.Experimental
TranylcypromineThe risk or severity of adverse effects can be increased when Tranylcypromine is combined with Phenytoin.Approved
Trastuzumab emtansineThe metabolism of Trastuzumab emtansine can be increased when combined with Phenytoin.Approved
TrazodoneThe serum concentration of Trazodone can be decreased when it is combined with Phenytoin.Approved, Investigational
TreprostinilThe serum concentration of Treprostinil can be decreased when it is combined with Phenytoin.Approved, Investigational
TretinoinThe metabolism of Tretinoin can be increased when combined with Phenytoin.Approved, Investigational, Nutraceutical
TriamcinoloneThe metabolism of Triamcinolone can be increased when combined with Phenytoin.Approved, Vet Approved
TriazolamThe serum concentration of Phenytoin can be increased when it is combined with Triazolam.Approved
TrifluoperazineThe serum concentration of Phenytoin can be increased when it is combined with Trifluoperazine.Approved
TriflupromazineThe serum concentration of Phenytoin can be increased when it is combined with Triflupromazine.Approved, Vet Approved
TrimethadioneThe metabolism of Trimethadione can be increased when combined with Phenytoin.Approved
TrimethoprimThe serum concentration of Phenytoin can be increased when it is combined with Trimethoprim.Approved, Vet Approved
TrimetrexateThe serum concentration of Phenytoin can be increased when it is combined with Trimetrexate.Approved, Investigational
TrimipramineThe metabolism of Trimipramine can be increased when combined with Phenytoin.Approved
TriprolidineThe risk or severity of adverse effects can be increased when Phenytoin is combined with Triprolidine.Approved
TroglitazoneThe metabolism of Troglitazone can be increased when combined with Phenytoin.Withdrawn
TroleandomycinThe metabolism of Troleandomycin can be increased when combined with Phenytoin.Approved
Uc1010The risk or severity of adverse effects can be increased when Phenytoin is combined with Uc1010.Investigational
UdenafilThe metabolism of Udenafil can be increased when combined with Phenytoin.Approved, Investigational
UlipristalThe serum concentration of Ulipristal can be decreased when it is combined with Phenytoin.Approved
ValdecoxibThe metabolism of Valdecoxib can be increased when combined with Phenytoin.Investigational, Withdrawn
Valproic AcidThe serum concentration of Phenytoin can be decreased when it is combined with Valproic Acid.Approved, Investigational
ValsartanThe metabolism of Valsartan can be increased when combined with Phenytoin.Approved, Investigational
VandetanibThe serum concentration of Vandetanib can be decreased when it is combined with Phenytoin.Approved
VanoxerineThe metabolism of Vanoxerine can be increased when combined with Phenytoin.Investigational
VardenafilThe metabolism of Vardenafil can be increased when combined with Phenytoin.Approved
VemurafenibThe serum concentration of Vemurafenib can be decreased when it is combined with Phenytoin.Approved
VenetoclaxThe metabolism of Venetoclax can be increased when combined with Phenytoin.Approved
VenlafaxineThe metabolism of Venlafaxine can be increased when combined with Phenytoin.Approved
VerapamilThe serum concentration of Phenytoin can be increased when it is combined with Verapamil.Approved
VicrivirocThe metabolism of Vicriviroc can be increased when combined with Phenytoin.Investigational
VigabatrinThe serum concentration of Phenytoin can be decreased when it is combined with Vigabatrin.Approved
VilanterolThe metabolism of Vilanterol can be increased when combined with Phenytoin.Approved
VilazodoneThe serum concentration of Vilazodone can be decreased when it is combined with Phenytoin.Approved
VinblastineThe metabolism of Vinblastine can be increased when combined with Phenytoin.Approved
VincristineThe serum concentration of Vincristine can be decreased when it is combined with Phenytoin.Approved, Investigational
VindesineThe serum concentration of Phenytoin can be decreased when it is combined with Vindesine.Approved
VinorelbineThe metabolism of Vinorelbine can be increased when combined with Phenytoin.Approved, Investigational
VinpocetineThe serum concentration of Phenytoin can be increased when it is combined with Vinpocetine.Investigational
VismodegibThe metabolism of Vismodegib can be increased when combined with Phenytoin.Approved
VorapaxarThe serum concentration of Vorapaxar can be decreased when it is combined with Phenytoin.Approved
VoriconazoleThe serum concentration of Phenytoin can be increased when it is combined with Voriconazole.Approved, Investigational
VortioxetineThe serum concentration of Vortioxetine can be decreased when it is combined with Phenytoin.Approved
WarfarinPhenytoin may increase the anticoagulant activities of Warfarin.Approved
XimelagatranThe metabolism of Ximelagatran can be increased when combined with Phenytoin.Approved, Investigational, Withdrawn
XylazineThe risk or severity of adverse effects can be increased when Xylazine is combined with Phenytoin.Vet Approved
XylometazolineThe serum concentration of Phenytoin can be increased when it is combined with Xylometazoline.Approved
YohimbineThe metabolism of Yohimbine can be increased when combined with Phenytoin.Approved, Vet Approved
ZafirlukastThe metabolism of Zafirlukast can be increased when combined with Phenytoin.Approved, Investigational
ZalcitabineThe metabolism of Zalcitabine can be increased when combined with Phenytoin.Approved
ZaleplonThe serum concentration of Zaleplon can be decreased when it is combined with Phenytoin.Approved, Illicit, Investigational
ZaltoprofenThe metabolism of Zaltoprofen can be increased when combined with Phenytoin.Approved
ZiconotideThe serum concentration of Phenytoin can be increased when it is combined with Ziconotide.Approved
ZidovudineThe metabolism of Zidovudine can be increased when combined with Phenytoin.Approved
ZileutonThe metabolism of Zileuton can be increased when combined with Phenytoin.Approved, Investigational, Withdrawn
ZimelidineThe serum concentration of Phenytoin can be increased when it is combined with Zimelidine.Withdrawn
ZiprasidoneThe metabolism of Ziprasidone can be increased when combined with Phenytoin.Approved
ZolazepamThe risk or severity of adverse effects can be increased when Zolazepam is combined with Phenytoin.Vet Approved
ZolpidemPhenytoin may increase the central nervous system depressant (CNS depressant) activities of Zolpidem.Approved
ZomepiracThe metabolism of Zomepirac can be increased when combined with Phenytoin.Withdrawn
ZonisamideThe serum concentration of Zonisamide can be decreased when it is combined with Phenytoin.Approved, Investigational
ZopicloneThe metabolism of Zopiclone can be increased when combined with Phenytoin.Approved
ZotepineThe risk or severity of adverse effects can be increased when Zotepine is combined with Phenytoin.Approved
ZuclopenthixolThe serum concentration of Zuclopenthixol can be decreased when it is combined with Phenytoin.Approved, Investigational
Food Interactions
  • Avoid alcohol.
  • Do not take calcium, aluminum, magnesium or Iron supplements within 2 hours of taking this medication.
  • Take with food to increase bioavailability and reduce irritation.
References
Synthesis Reference

Mahdi B. Fawzi, Anne K. Taylor, “Parenteral phenytoin preparations.” U.S. Patent US4642316, issued April, 1981.

US4642316
General References
  1. Link [Link]
External Links
ATC CodesN03AB02N03AB52
AHFS Codes
  • 28:12.12
PDB EntriesNot Available
FDA labelNot Available
MSDSDownload (73.7 KB)
ADMET
Predicted ADMET features
PropertyValueProbability
Human Intestinal Absorption+0.9909
Blood Brain Barrier+0.976
Caco-2 permeable+0.8867
P-glycoprotein substrateNon-substrate0.5593
P-glycoprotein inhibitor INon-inhibitor0.8782
P-glycoprotein inhibitor IINon-inhibitor0.987
Renal organic cation transporterNon-inhibitor0.8995
CYP450 2C9 substrateNon-substrate0.733
CYP450 2D6 substrateSubstrate0.8911
CYP450 3A4 substrateNon-substrate0.7591
CYP450 1A2 substrateNon-inhibitor0.9045
CYP450 2C9 inhibitorNon-inhibitor0.8304
CYP450 2D6 inhibitorNon-inhibitor0.935
CYP450 2C19 inhibitorNon-inhibitor0.9026
CYP450 3A4 inhibitorNon-inhibitor0.8309
CYP450 inhibitory promiscuityLow CYP Inhibitory Promiscuity0.8994
Ames testNon AMES toxic0.9132
CarcinogenicityNon-carcinogens0.855
BiodegradationNot ready biodegradable0.992
Rat acute toxicity2.1567 LD50, mol/kg Not applicable
hERG inhibition (predictor I)Weak inhibitor0.9793
hERG inhibition (predictor II)Non-inhibitor0.8916
ADMET data is predicted using admetSAR, a free tool for evaluating chemical ADMET properties. (23092397 )
Pharmacoeconomics
Manufacturers
  • Parke davis div warner lambert co
  • Actavis mid atlantic llc
  • Taro pharmaceutical industries ltd
  • Vistapharm inc
  • Wockhardt eu operations (swiss) ag
  • Pfizer pharmaceuticals ltd
  • Lannett co inc
  • Amneal pharmaceuticals ny llc
  • Barr laboratories inc
  • Mylan pharmaceuticals inc
  • Pliva inc
  • Sun pharmaceutical industries ltd
  • Wockhardt ltd
  • Wockhardt usa inc
  • Watson laboratories inc
  • Pharmeral inc
  • Ivax pharmaceuticals inc sub teva pharmaceuticals usa
  • Parke davis pharmaceutical research div warner lambert co
  • App pharmaceuticals llc
  • Baxter healthcare corp
  • Hikma farmaceutica (portugal) sa
  • Hospira inc
  • Marsam pharmaceuticals llc
  • Pharmaforce inc
  • Smith and nephew solopak div smith and nephew
  • Solopak medical products inc
  • Warner chilcott div warner lambert co
Packagers
Dosage forms
FormRouteStrength
Capsule, extended releaseOral30 mg/1
CapsuleOral100 mg
CapsuleOral30 mg
TabletOral50 mg
LiquidIntramuscular; Intravenous250 mg
CapsuleOral
SuspensionOral125 mg
SuspensionOral30 mg
Capsule, extended releaseOral200 mg/1
Capsule, extended releaseOral300 mg/1
SuspensionOral100 mg/4mL
SuspensionOral125 mg/5mL
Tablet, chewableOral50 mg/1
CapsuleOral100 mg/1
Capsule, extended releaseOral100 mg/1
InjectionIntramuscular; Intravenous50 mg/mL
InjectionIntravenous50 mg/mL
Injection, solutionIntramuscular; Intravenous250 mg/5mL
Injection, solutionIntramuscular; Intravenous50 mg/mL
SolutionIntramuscular; Intravenous50 mg
LiquidIntramuscular; Intravenous50 mg
Prices
Unit descriptionCostUnit
Dilantin 125 mg/5ml Suspension 237ml Bottle69.28USD bottle
Phenytoin Sodium 50 mg/ml2.64USD ml
Phenytek 300 mg capsule1.47USD capsule
Phenytoin sod ext 300 mg capsule1.2USD capsule
Phenytoin sodium powder1.16USD g
Phenytek 200 mg capsule0.98USD capsule
Phenytoin 50 mg/ml ampul0.96USD ml
Phenytoin sod ext 200 mg capsule0.8USD capsule
Phenytoin 50 mg/ml vial0.67USD ml
Phenytoin 100 mg/2 ml vial0.6USD ml
Dilantin Infatabs 50 mg Chew Tabs0.6USD tab
Dilantin 100 mg capsule0.51USD capsule
Phenytoin 100 mg/4 ml susp0.48USD ml
Dilantin 30 mg capsule0.46USD capsule
Phenytoin 250 mg/5 ml vial0.45USD ml
Dilantin 50 mg infatab0.44USD each
Dilantin 100 mg kapseal0.39USD each
Dilantin 30 mg kapseal0.39USD each
Phenytoin Sodium Extended 100 mg capsule0.36USD capsule
Phenytoin sod ext 100 mg capsule0.34USD capsule
Phenytoin powder0.23USD g
Phenytoin 125 mg/5ml Suspension0.15USD ml
Dilantin Infatabs 50 mg Chewable Tablet0.08USD tablet
Dilantin 100 mg Capsule0.08USD capsule
Dilantin 30 mg Capsule0.06USD capsule
Dilantin-125 25 mg/ml Suspension0.05USD ml
Dilantin-30 6 mg/ml Suspension0.04USD ml
Taro-Phenytoin 25 mg/ml Suspension0.03USD ml
DrugBank does not sell nor buy drugs. Pricing information is supplied for informational purposes only.
PatentsNot Available
Properties
StateSolid
Experimental Properties
PropertyValueSource
melting point286 °CPhysProp
water solubility32 mg/L (at 22 °C)YALKOWSKY,SH & DANNENFELSER,RM (1992)
logP2.47HANSCH,C ET AL. (1995)
Caco2 permeability-4.57ADME Research, USCD
pKa8.33SANGSTER (1994)
Predicted Properties
PropertyValueSource
Water Solubility0.0711 mg/mLALOGPS
logP2.26ALOGPS
logP2.15ChemAxon
logS-3.5ALOGPS
pKa (Strongest Acidic)9.47ChemAxon
pKa (Strongest Basic)-9ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count2ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area58.2 Å2ChemAxon
Rotatable Bond Count2ChemAxon
Refractivity70.18 m3·mol-1ChemAxon
Polarizability25.48 Å3ChemAxon
Number of Rings3ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Mass Spec (NIST)Download (9.46 KB)
Spectra
Spectrum TypeDescriptionSplash Key
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, NegativeNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, NegativeNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, NegativeNot Available
MSMass Spectrum (Electron Ionization)splash10-0f89-4940000000-2a0dda513d9f63dc6610View in MoNA
1D NMR1H NMR SpectrumNot Available
1D NMR13C NMR SpectrumNot Available
Taxonomy
DescriptionThis compound belongs to the class of organic compounds known as phenylhydantoins. These are heterocyclic aromatic compounds containing an imiazolidinedione moiety substituted by a phenyl group.
KingdomOrganic compounds
Super ClassOrganoheterocyclic compounds
ClassAzolidines
Sub ClassImidazolidines
Direct ParentPhenylhydantoins
Alternative Parents
Substituents
  • 5-phenylhydantoin
  • Diphenylmethane
  • Phenylimidazolidine
  • 5-monosubstituted hydantoin
  • Ureide
  • Benzenoid
  • Monocyclic benzene moiety
  • Urea
  • Carboxamide group
  • Azacycle
  • Carboxylic acid derivative
  • Hydrocarbon derivative
  • Organooxygen compound
  • Organonitrogen compound
  • Carbonyl group
  • Aromatic heteromonocyclic compound
Molecular FrameworkAromatic heteromonocyclic compounds
External Descriptors

Targets

Kind
Protein
Organism
Human
Pharmacological action
yes
Actions
inhibitor
General Function:
Voltage-gated sodium channel activity involved in sa node cell action potential
Specific Function:
This protein mediates the voltage-dependent sodium ion permeability of excitable membranes. Assuming opened or closed conformations in response to the voltage difference across the membrane, the protein forms a sodium-selective channel through which Na(+) ions may pass in accordance with their electrochemical gradient. It is a tetrodotoxin-resistant Na(+) channel isoform. This channel is respon...
Gene Name:
SCN5A
Uniprot ID:
Q14524
Molecular Weight:
226937.475 Da
References
  1. Mitiushin VM, Kozyreva EV: [Several types of mitochondrial ultrastructure in animal cell mitochondria and their relationship to energy production]. Tsitologiia. 1978 Apr;20(4):371-9. [PubMed:150666 ]
  2. Swadron SP, Rudis MI, Azimian K, Beringer P, Fort D, Orlinsky M: A comparison of phenytoin-loading techniques in the emergency department. Acad Emerg Med. 2004 Mar;11(3):244-52. [PubMed:15001403 ]
Kind
Protein
Organism
Human
Pharmacological action
yes
Actions
inhibitor
General Function:
Voltage-gated sodium channel activity
Specific Function:
Mediates the voltage-dependent sodium ion permeability of excitable membranes. Assuming opened or closed conformations in response to the voltage difference across the membrane, the protein forms a sodium-selective channel through which Na(+) ions may pass in accordance with their electrochemical gradient.
Gene Name:
SCN1A
Uniprot ID:
P35498
Molecular Weight:
228969.49 Da
References
  1. Tate SK, Depondt C, Sisodiya SM, Cavalleri GL, Schorge S, Soranzo N, Thom M, Sen A, Shorvon SD, Sander JW, Wood NW, Goldstein DB: Genetic predictors of the maximum doses patients receive during clinical use of the anti-epileptic drugs carbamazepine and phenytoin. Proc Natl Acad Sci U S A. 2005 Apr 12;102(15):5507-12. Epub 2005 Apr 1. [PubMed:15805193 ]
  2. Tate SK, Singh R, Hung CC, Tai JJ, Depondt C, Cavalleri GL, Sisodiya SM, Goldstein DB, Liou HH: A common polymorphism in the SCN1A gene associates with phenytoin serum levels at maintenance dose. Pharmacogenet Genomics. 2006 Oct;16(10):721-6. [PubMed:17001291 ]
  3. Mantegazza M, Curia G, Biagini G, Ragsdale DS, Avoli M: Voltage-gated sodium channels as therapeutic targets in epilepsy and other neurological disorders. Lancet Neurol. 2010 Apr;9(4):413-24. doi: 10.1016/S1474-4422(10)70059-4. [PubMed:20298965 ]

Enzymes

Kind
Protein
Organism
Human
Pharmacological action
unknown
Actions
substrateinhibitorinducer
General Function:
Steroid hydroxylase activity
Specific Function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics. This enzyme contributes to the wide pharmacokinetics variability of the metabolism of drugs such as S-warfarin, diclofenac, phenyto...
Gene Name:
CYP2C9
Uniprot ID:
P11712
Molecular Weight:
55627.365 Da
References
  1. Levy RH: Cytochrome P450 isozymes and antiepileptic drug interactions. Epilepsia. 1995;36 Suppl 5:S8-13. [PubMed:8806399 ]
  2. Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [PubMed:19515014 ]
  3. Tate SK, Depondt C, Sisodiya SM, Cavalleri GL, Schorge S, Soranzo N, Thom M, Sen A, Shorvon SD, Sander JW, Wood NW, Goldstein DB: Genetic predictors of the maximum doses patients receive during clinical use of the anti-epileptic drugs carbamazepine and phenytoin. Proc Natl Acad Sci U S A. 2005 Apr 12;102(15):5507-12. Epub 2005 Apr 1. [PubMed:15805193 ]
  4. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. doi: 10.1093/nar/gkp970. Epub 2009 Nov 24. [PubMed:19934256 ]
  5. Komatsu T, Yamazaki H, Asahi S, Gillam EM, Guengerich FP, Nakajima M, Yokoi T: Formation of a dihydroxy metabolite of phenytoin in human liver microsomes/cytosol: roles of cytochromes P450 2C9, 2C19, and 3A4. Drug Metab Dispos. 2000 Nov;28(11):1361-8. [PubMed:11038165 ]
  6. Drug Interactions: Cytochrome P450 Drug Interaction Table [Link]
Kind
Protein
Organism
Human
Pharmacological action
unknown
Actions
substrateinducer
General Function:
Steroid hydroxylase activity
Specific Function:
Responsible for the metabolism of a number of therapeutic agents such as the anticonvulsant drug S-mephenytoin, omeprazole, proguanil, certain barbiturates, diazepam, propranolol, citalopram and imipramine.
Gene Name:
CYP2C19
Uniprot ID:
P33261
Molecular Weight:
55930.545 Da
References
  1. Levy RH: Cytochrome P450 isozymes and antiepileptic drug interactions. Epilepsia. 1995;36 Suppl 5:S8-13. [PubMed:8806399 ]
  2. Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [PubMed:19515014 ]
  3. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. doi: 10.1093/nar/gkp970. Epub 2009 Nov 24. [PubMed:19934256 ]
  4. Komatsu T, Yamazaki H, Asahi S, Gillam EM, Guengerich FP, Nakajima M, Yokoi T: Formation of a dihydroxy metabolite of phenytoin in human liver microsomes/cytosol: roles of cytochromes P450 2C9, 2C19, and 3A4. Drug Metab Dispos. 2000 Nov;28(11):1361-8. [PubMed:11038165 ]
  5. Kaminsky LS, Zhang ZY: Human P450 metabolism of warfarin. Pharmacol Ther. 1997;73(1):67-74. [PubMed:9014207 ]
  6. Drug Interactions: Cytochrome P450 Drug Interaction Table [Link]
Kind
Protein
Organism
Human
Pharmacological action
unknown
Actions
substrateinducer
General Function:
Steroid hydroxylase activity
Specific Function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics. In the epoxidation of arachidonic acid it generates only 14,15- and 11,12-cis-epoxyeicosatrienoic acids. It is the principal enzyme...
Gene Name:
CYP2C8
Uniprot ID:
P10632
Molecular Weight:
55824.275 Da
References
  1. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. doi: 10.1093/nar/gkp970. Epub 2009 Nov 24. [PubMed:19934256 ]
  2. Drug Interactions: Cytochrome P450 Drug Interaction Table [Link]
Kind
Protein
Organism
Human
Pharmacological action
unknown
Actions
inducer
General Function:
Steroid hydroxylase activity
Specific Function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics. Acts as a 1,4-cineole 2-exo-monooxygenase.
Gene Name:
CYP2B6
Uniprot ID:
P20813
Molecular Weight:
56277.81 Da
References
  1. Drug Interactions: Cytochrome P450 Drug Interaction Table [Link]
Kind
Protein
Organism
Human
Pharmacological action
unknown
Actions
substrateinducer
General Function:
Vitamin d3 25-hydroxylase activity
Specific Function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It performs a variety of oxidation reactions (e.g. caffeine 8-oxidation, omeprazole sulphoxidation, midazolam 1'-hydroxylation and midazolam 4-hydroxylation) of structurally unrelated compounds, including steroids, fatty acids, and xenobiot...
Gene Name:
CYP3A4
Uniprot ID:
P08684
Molecular Weight:
57342.67 Da
References
  1. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. doi: 10.1093/nar/gkp970. Epub 2009 Nov 24. [PubMed:19934256 ]
Kind
Protein
Organism
Human
Pharmacological action
unknown
Actions
substrate
General Function:
Steroid hydroxylase activity
Specific Function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics.
Gene Name:
CYP2C18
Uniprot ID:
P33260
Molecular Weight:
55710.075 Da
References
  1. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. doi: 10.1093/nar/gkp970. Epub 2009 Nov 24. [PubMed:19934256 ]
Kind
Protein
Organism
Human
Pharmacological action
unknown
Actions
inducer
General Function:
Oxygen binding
Specific Function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics.
Gene Name:
CYP3A5
Uniprot ID:
P20815
Molecular Weight:
57108.065 Da
References
  1. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. doi: 10.1093/nar/gkp970. Epub 2009 Nov 24. [PubMed:19934256 ]
Kind
Protein
Organism
Human
Pharmacological action
unknown
Actions
inducer
General Function:
Oxygen binding
Specific Function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics.
Gene Name:
CYP3A7
Uniprot ID:
P24462
Molecular Weight:
57525.03 Da
References
  1. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. doi: 10.1093/nar/gkp970. Epub 2009 Nov 24. [PubMed:19934256 ]
Kind
Protein
Organism
Human
Pharmacological action
unknown
Actions
inhibitor
General Function:
Steroid 11-beta-monooxygenase activity
Specific Function:
Has steroid 11-beta-hydroxylase activity. In addition to this activity, the 18 or 19-hydroxylation of steroids and the aromatization of androstendione to estrone have also been ascribed to cytochrome P450 XIB.
Gene Name:
CYP11B1
Uniprot ID:
P15538
Molecular Weight:
57572.44 Da
References
  1. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. doi: 10.1093/nar/gkp970. Epub 2009 Nov 24. [PubMed:19934256 ]

Carriers

Kind
Protein
Organism
Human
Pharmacological action
unknown
General Function:
Toxic substance binding
Specific Function:
Serum albumin, the main protein of plasma, has a good binding capacity for water, Ca(2+), Na(+), K(+), fatty acids, hormones, bilirubin and drugs. Its main function is the regulation of the colloidal osmotic pressure of blood. Major zinc transporter in plasma, typically binds about 80% of all plasma zinc.
Gene Name:
ALB
Uniprot ID:
P02768
Molecular Weight:
69365.94 Da
References
  1. Chen J, Ohnmacht C, Hage DS: Studies of phenytoin binding to human serum albumin by high-performance affinity chromatography. J Chromatogr B Analyt Technol Biomed Life Sci. 2004 Sep 25;809(1):137-45. [PubMed:15282104 ]
  2. Ohnmacht CM, Chen S, Tong Z, Hage DS: Studies by biointeraction chromatography of binding by phenytoin metabolites to human serum albumin. J Chromatogr B Analyt Technol Biomed Life Sci. 2006 May 19;836(1-2):83-91. Epub 2006 Apr 18. [PubMed:16621742 ]

Transporters

Kind
Protein
Organism
Human
Pharmacological action
unknown
Actions
inhibitor
General Function:
Thyroid hormone transmembrane transporter activity
Specific Function:
Mediates the Na(+)-independent high affinity transport of organic anions such as the thyroid hormones thyroxine (T4) and rT3. Other potential substrates, such as triiodothyronine (T3), 17-beta-glucuronosyl estradiol, estrone-3-sulfate and sulfobromophthalein (BSP) are transported with much lower efficiency. May play a signifiant role in regulating T4 flux into and out of the brain (By similarity).
Gene Name:
SLCO1C1
Uniprot ID:
Q9NYB5
Molecular Weight:
78695.625 Da
References
  1. Westholm DE, Stenehjem DD, Rumbley JN, Drewes LR, Anderson GW: Competitive inhibition of organic anion transporting polypeptide 1c1-mediated thyroxine transport by the fenamate class of nonsteroidal antiinflammatory drugs. Endocrinology. 2009 Feb;150(2):1025-32. doi: 10.1210/en.2008-0188. Epub 2008 Oct 9. [PubMed:18845642 ]
  2. Berman HM, Westbrook J, Feng Z, Gilliland G, Bhat TN, Weissig H, Shindyalov IN, Bourne PE: The Protein Data Bank. Nucleic Acids Res. 2000 Jan 1;28(1):235-42. [PubMed:10592235 ]
Kind
Protein
Organism
Human
Pharmacological action
unknown
Actions
substrate
General Function:
Xenobiotic-transporting atpase activity
Specific Function:
Energy-dependent efflux pump responsible for decreased drug accumulation in multidrug-resistant cells.
Gene Name:
ABCB1
Uniprot ID:
P08183
Molecular Weight:
141477.255 Da
References
  1. Baltes S, Gastens AM, Fedrowitz M, Potschka H, Kaever V, Loscher W: Differences in the transport of the antiepileptic drugs phenytoin, levetiracetam and carbamazepine by human and mouse P-glycoprotein. Neuropharmacology. 2007 Feb;52(2):333-46. Epub 2006 Oct 10. [PubMed:17045309 ]
  2. Luna-Tortos C, Fedrowitz M, Loscher W: Several major antiepileptic drugs are substrates for human P-glycoprotein. Neuropharmacology. 2008 Dec;55(8):1364-75. doi: 10.1016/j.neuropharm.2008.08.032. Epub 2008 Sep 11. [PubMed:18824002 ]
Kind
Protein
Organism
Human
Pharmacological action
unknown
Actions
substrate
General Function:
Organic anion transmembrane transporter activity
Specific Function:
Mediates hepatobiliary excretion of numerous organic anions. May function as a cellular cisplatin transporter.
Gene Name:
ABCC2
Uniprot ID:
Q92887
Molecular Weight:
174205.64 Da
References
  1. Baltes S, Gastens AM, Fedrowitz M, Potschka H, Kaever V, Loscher W: Differences in the transport of the antiepileptic drugs phenytoin, levetiracetam and carbamazepine by human and mouse P-glycoprotein. Neuropharmacology. 2007 Feb;52(2):333-46. Epub 2006 Oct 10. [PubMed:17045309 ]
Comments
comments powered by Disqus
Drug created on June 13, 2005 07:24 / Updated on December 08, 2016 11:11