Logo pink
Are you a
new drug developer?
Contact us to learn more about our customized products and solutions.
Accession Number
DB01068  (APRD00054)
Small Molecule
Approved, Illicit

A benzodiazepine used to treat various seizures, including myotonic or atonic seizures, photosensitive epilepsy, and absence seizures, although tolerance may develop [Label] [11, 12, 13, 14]. The agent has also been indicated for treating panic disorder [Label] [7, 11, 12, 13, 14]. The mechanism of action appears to involve the enhancement of gamma-aminobutyric acid receptor responses [Label] [7, 8, 11, 12, 13, 14].

Since being first patented in 1960 and then released for sale from Roche in the US in 1975 [9, 10], clonazepam has experienced a storied history in the treatment of the aforementioned medical conditions. Now available as a generic medication, the agent continues to see exceptionally high use as millions of prescriptions are written for the medication internationally every year. Unfortunately, however, like most benzodiazepines, clonazepam use has also been associated with recreational use and drug abuse [Label] [11, 12, 13, 14].

  • 1,3-dihydro-7-nitro-5-(2-chlorophenyl)-2H-1,4.benzodiazepin-2-one
  • 5-(2-chloro-phenyl)-7-nitro-1,3-dihydro-benzo[e][1,4]diazepin-2-one
  • 5-(2-chlorophenyl)-7-nitro-1H-benzo[e][1,4]diazepin-2(3H)-one
  • 5-(o-chlorophenyl)-7-nitro-1,3-dihydro-2H-1,4-benzodiazepin-2-one
  • Clonazepam
  • Clonazepamum
External IDs
RO 5-4023 / RO-5-4023
Product Images
Prescription Products
NameDosageStrengthRouteLabellerMarketing StartMarketing End
ClonapamTablet0.5 mgOralValeant Canada Lp Valeant Canada S.E.C.1997-01-31Not applicableCanada
ClonapamTablet1.0 mgOralValeant Canada Lp Valeant Canada S.E.C.1997-01-31Not applicableCanada
ClonapamTablet2.0 mgOralValeant Canada Lp Valeant Canada S.E.C.1997-02-28Not applicableCanada
ClonazepamTablet0.25 mgOralSivem Pharmaceuticals Ulc2015-07-09Not applicableCanada
ClonazepamTablet2 mgOralSivem Pharmaceuticals Ulc2015-07-09Not applicableCanada
ClonazepamTablet0.5 mg/1OralWatson Pharmaceuticals2008-03-18Not applicableUs
ClonazepamTablet1 mg/1OralWatson Pharmaceuticals2008-03-18Not applicableUs
ClonazepamTablet2 mg/1OralWatson Pharmaceuticals2008-03-18Not applicableUs
ClonazepamTablet1 mgOralMeliapharm Inc2010-10-202014-06-25Canada
ClonazepamTablet2 mgOralMeliapharm Inc2010-10-202014-06-25Canada
Generic Prescription Products
NameDosageStrengthRouteLabellerMarketing StartMarketing End
Accel-clonazepamTablet0.5 mgOralAccel Pharma IncNot applicableNot applicableCanada
Accel-clonazepamTablet1.0 mgOralAccel Pharma IncNot applicableNot applicableCanada
Accel-clonazepamTablet2.0 mgOralAccel Pharma IncNot applicableNot applicableCanada
Apo-clonazepam - Tab 0.5mgTablet.5 mgOralApotex Corporation1995-12-31Not applicableCanada
Apo-clonazepam - Tab 2mgTablet2 mgOralApotex Corporation1995-12-31Not applicableCanada
ClonazepamTablet0.5 mg/1OralEon Labs, Inc.1997-08-292021-08-31Us
ClonazepamTablet1 mg/1OralPreferreed Pharmaceuticals Inc.2012-01-17Not applicableUs
ClonazepamTablet1 mg/1OralEon Labs, Inc.1997-08-292021-04-30Us
ClonazepamTablet2 mg/1OralEon Labs, Inc.1997-08-292021-04-30Us
ClonazepamTablet0.5 mg/1Oralbryant ranch prepack2006-06-282018-04-30Us63629 134120180907 15195 8dkmlz
International/Other Brands
Antelepsin (AWD) / Iktorivil (Roche) / Rivotril (Roche)
CAS number
Average: 315.711
Monoisotopic: 315.041068908
Chemical Formula
InChI Key



Clonazepam is indicated as monotherapy or as an adjunct in the treatment of Lennox-Gastaut syndrome (petit mal variant), akinetic, and myoclonic seizures [Label] [13]. Furthermore, clonazepam may also be of some value in patients with absence spells (petit mal) who have failed to respond to succinimides [Label] [13]. Additionally, clonazepam is also indicated for the treatment of panic disorder, with or without agoraphobia, as defined in the DSM-V [Label].

Alternatively, some regional prescribing information note that clonazepam is indicated for all clinical forms of epileptic disease and seizures in adults, especially absence seizures (petit mal) including atypical absence; primary or secondarily generalised tonic-clonic (grand mal), tonic or clonic seizures; partial (focal) seizures with elementary or complex symptomatology; various forms of myoclonic seizures, myoclonus and associated abnormal movements [11, 14]. Such regional label data also has clonazepam indicated for most types of epilepsy in infants and children, especially absences (petit mal), myoclonic seizures and tonic-clonic fits, whether due to primary generalized epilepsy or to secondary generalization of partial epilepsy [14].

Associated Conditions

The pharmacodynamic properties of clonazepam are common among benzodiazepines and include anticonvulsive, sedative, muscle relaxing and anxiolytic effects [6, 11, 12, 13]. Animal data and electroencephalographic investigations in man have shown that clonazepam rapidly suppresses many types of paroxysmal activity including the spike and wave discharge in absence seizures (petit mal), slow spike wave, generalized spike wave, spikes with temporal or other locations, as well as irregular spikes and waves [Label] [6, 11, 12, 13]. Moreover, the agent can also decrease the frequency, amplitude, duration, and spread of discharge in minor motor seizures [Label] [12].

Generalized EEG abnormalities are more readily suppressed by clonazepam than are focal EEG abnormalities such as focal spikes [11]. Clonazepam has beneficial effects in generalized and focal epilepsies [11].

Mechanism of action

Gamma-Aminobutyric acid (GABA) is considered the principal inhibitory neurotransmitter in the human body [6, 7, 8]. When GABA binds to GABA(a) receptors found in neuron synapses, chloride ions are conducted across neuron cell membranes via an ion channel in the receptors [6, 7, 8, 13]. With enough chloride ions conducted, the local, associated neuron membrane potentials are hyperpolarized - making it more difficult or less likely for action potentials to fire, ultimately resulting in less excitation of the neurons [6, 7, 8, 13].

Subsequently, benzodiazepines like clonazepam can bind to benzodiazepine receptors that are components of various varieties of GABA(a) receptors [6, 7, 8, 13, 11, 12]. This binding acts to enhance the effects of GABA by increasing GABA affinity for the GABA(a) receptor, which ultimately enhances GABA ligand binding at the receptors [6, 7, 8, 13, 11, 12]. This enhanced ligand binding of the inhibitory neurotransmitter GABA to the receptors increases the aforementioned chloride ion conduction (perhaps reportedly via an increase in the frequency of the chloride channel opening), resulting in a hyperpolarized cell membrane that prevents further excitation of the associated neuron cells [6, 7, 8, 13, 11, 12]. Combined with the notion that such benzodiazepine receptor associated GABA(a) receptors exist both peripherally and in the CNS, this activity consequently facilitates various effects like sedation, hypnosis, skeletal muscle relaxation, anticonvulsant activity, and anxiolytic action [6, 7, 8, 13, 11, 12].

In particular, when out of the ordinary rapid and repetitive electrical signals are released in the CNS, it is proposed that the brain can become over-stimulated and ordinary functions are disrupted - resulting in seizure activity [8]. By enhancing the neuro-inhibitory activity of GABA, it is believed that clonazepam can facilitate in decreasing any excessive electrical nerve activity in the CNS that might be contributing to seizures [8]. Concurrently, it is also believed that clonazepam's actions in enhancing GABA effects may inhibit neuronal activity proposed to occur in amygdala-centered fear circuits - therefore assisting in the management of anxiety or panic [7].

AGABA-A receptor (anion channel)
positive allosteric modulator
UTranslocator protein
UNuclear receptor subfamily 1 group I member 2
partial agonist

Clonazepam is rapidly and almost entirely absorbed after oral administration as tablets [Label] [12, 14]. Peak plasma concentrations of clonazepam administered by the oral route are reached within 1-4 hours and the associated absorption half-life is about 25 minutes [Label] [12, 14]. The absolute bioavailability is approximately 90% - but with substantially large differences between individuals [Label] [12, 14].

Volume of distribution

Clonazepam distributes very rapidly to various organs and body tissues with preferential uptake by brain structures [12, 14]. The apparent volume of distribution has been documented as approximately 3 L/kg [12, 14].

Protein binding

The recorded plasma protein binding of clonazepam ranges between 82–86% [12, 14].


Clonazepam is metabolized principally in the liver [12, 14]. The metabolic pathways include hydroxylation, reduction of the nitro groups to amine groups, and the addition of acetate to the amino grouping [12, 14]. In particular, clonazepam is extensively metabolized by reduction to 7-amino-clonazepam and by N-acetylation to 7-acetamido-clonazepam [12, 14]. Hydroxylation at the C-3 position also occurs [12, 14]. Hepatic cytochrome P450 3A4 is implicated in the nitroreduction of clonazepam to pharmacologically inactive metabolites [12, 14].

Route of elimination

Approximately 50-70% of a clonazepam dose is excreted in the urine and 10-30% is excreted in the feces as metabolites [12, 14]. The excretion of unchanged clonazepam in the urine is typically less than 2% of the administered dose [12, 14]. Metabolites of clonazepam are present in urine as both free and conjugated (glucuronide and sulfate) compounds [12, 14].

Half life

The mean elimination half-life determined for clonazepam is independent of the dose given and has been documented as being about 30-40 hours [12, 14].


The documented clearance for clonazepam is approximately 55 ml/min regardless of gender [12]. Nevertheless, clearance values normalized by weight decline with increasing body weight [12].


Benzodiazepines like clonazepam commonly cause drowsiness, ataxia, dysarthria, and nystagmus. Overdose with clonazepam is generally not life-threatening if the drug is taken alone, but may lead to areflexia, apnea, hypotension, cardiorespiratory depression, and coma. Coma, if it does occur, usually lasts a few hours but it can become more protracted and cyclical, especially in elderly patients. Increased frequency of seizures may occur in patients at supratherapeutic plasma concentrations. Benzodiazepine respiratory depressant effects are more serious when compounded in patients with respiratory disease.

An increased risk of congenital malformations associated with the use of benzodiazepine drugs like clonazepam has been suggested in several studies [Label] [12, 14]. There may also be non-teratogenic risks associated with the use of benzodiazepines during pregnancy [Label] [12, 14]. There have been reports of neonatal flaccidity, respiratory and feeding difficulties, and hypothermia in children born to mothers who have been receiving benzodiazepines late in pregnancy [Label] [12, 14]. In addition, children born to mothers receiving benzodiazepines late in pregnancy may be at some risk of experiencing withdrawal symptoms during the postnatal period [Label] [12, 14]. In general, it is best for patients who are of childbearing potential and also use benzodiazepines like clonazepam to discuss such matters with their health care professionals as careful consideration must be undertaken regarding the intersection of the risks of untreated seizure potential in the patient and any possible toxicity to the fetus [Label] [12, 14].

Although the active ingredient of clonazepam has been found to pass into the maternal milk in small amounts only, mothers receiving clonazepam should not breast-feed their infants [Label] [12, 14].

Since the possibility that adverse effects on the physical or mental development of the child could become apparent only after a number of years, the risk-benefit consideration of the long-term use of clonazepam in pediatric patients younger than five years of age is important [Label] [12, 14].

The pharmacological effects of benzodiazepines like clonazepam appear to be greater in elderly patients than in younger patients even at similar plasma benzodiazepine concentrations, possibly because of age-related changes in drug-receptor interactions, post-receptor mechanisms, and organ function [Label] [12, 14]. In general elderly patients should be started on the lowest possible dose of clonazepam and observed closely [Label] [12, 14]. There is an increased risk for falls and fractures among elderly and debilitated benzodiazepine users [Label] [12, 14]. The risk is increased in those taking concomitant sedatives, including substances like benzodiazepines, alcoholic beverages, and so on [Label] [12, 14].

Some oral LD50 values documented are >4000 mg/kg for the mouse model, >4000 mg/kg for the adult rat model, and >2000 mg/kg for the rabbit model [12].

Affected organisms
  • Humans and other mammals
Not Available
Pharmacogenomic Effects/ADRs
Not Available


Drug Interactions
(R)-warfarinThe metabolism of (R)-warfarin can be decreased when combined with Clonazepam.
(S)-WarfarinThe metabolism of (S)-Warfarin can be decreased when combined with Clonazepam.
2,5-Dimethoxy-4-ethylthioamphetamineThe risk or severity of adverse effects can be increased when Clonazepam is combined with 2,5-Dimethoxy-4-ethylthioamphetamine.
3-isobutyl-1-methyl-7H-xanthineThe therapeutic efficacy of Clonazepam can be decreased when used in combination with 3-isobutyl-1-methyl-7H-xanthine.
3,5-diiodothyropropionic acidThe metabolism of 3,5-diiodothyropropionic acid can be decreased when combined with Clonazepam.
4-Bromo-2,5-dimethoxyamphetamineThe risk or severity of adverse effects can be increased when Clonazepam is combined with 4-Bromo-2,5-dimethoxyamphetamine.
4-hydroxycoumarinThe metabolism of 4-hydroxycoumarin can be decreased when combined with Clonazepam.
4-MethoxyamphetamineThe risk or severity of adverse effects can be increased when Clonazepam is combined with 4-Methoxyamphetamine.
5-androstenedioneThe metabolism of 5-androstenedione can be decreased when combined with Clonazepam.
5-methoxy-N,N-dimethyltryptamineThe risk or severity of adverse effects can be increased when Clonazepam is combined with 5-methoxy-N,N-dimethyltryptamine.
Food Interactions
  • Avoid alcohol.
  • Avoid excessive quantities of coffee or tea (Caffeine).
  • Take without regard to meals.


Synthesis Reference

Kariss, J. and Newmark, H.L.; US. Patents 3,116,203; December 31, 1963; and 3,123,529; March 3, 1964; both assigned to Hoffmann-LaRoche, Inc. Keller, O., Steiger, N. and Sternbach, L.H.; U S . Patents 3,121,114; February 11, 1964; and 3,203890; August 31, 1965; both assigned to Hoffmann-LaRoche, Inc. Focella, A. and Rachlin, A.I.; U.S. Patent 3,335,181; August 8, 1967; assigned to Hoffmann- LaRoche. Inc.

General References
  1. Dreifuss FE, Penry JK, Rose SW, Kupferberg HJ, Dyken P, Sato S: Serum clonazepam concentrations in children with absence seizures. Neurology. 1975 Mar;25(3):255-8. [PubMed:1089913]
  2. Robertson MD, Drummer OH: Postmortem drug metabolism by bacteria. J Forensic Sci. 1995 May;40(3):382-6. [PubMed:7782744]
  3. Rosen GM, Turner MJ 3rd: Synthesis of spin traps specific for hydroxyl radical. J Med Chem. 1988 Feb;31(2):428-32. [PubMed:2828624]
  4. Rosen GM, Demos HA, Rauckman EJ: Not all aromatic nitro compounds form free radicals. Toxicol Lett. 1984 Aug;22(2):145-52. [PubMed:6089382]
  5. Earley JV, Fryer RI, Ning RY: Quinazolines and 1,4-benzodiazepines. LXXXIX: Haptens useful in benzodiazepine immunoassay development. J Pharm Sci. 1979 Jul;68(7):845-50. [PubMed:458601]
  6. DeVane CL, Ware MR, Lydiard RB: Pharmacokinetics, pharmacodynamics, and treatment issues of benzodiazepines: alprazolam, adinazolam, and clonazepam. Psychopharmacol Bull. 1991;27(4):463-73. [PubMed:1687613]
  7. Nardi AE, Machado S, Almada LF, Paes F, Silva AC, Marques RJ, Amrein R, Freire RC, Martin-Santos R, Cosci F, Hallak JE, Crippa JA, Arias-Carrion O: Clonazepam for the treatment of panic disorder. Curr Drug Targets. 2013 Mar;14(3):353-64. [PubMed:23256724]
  8. Jenner P, Pratt JA, Marsden CD: Mechanism of action of clonazepam in myoclonus in relation to effects on GABA and 5-HT. Adv Neurol. 1986;43:629-43. [PubMed:2418652]
  9. Fischer, Jnos; Ganellin, C. Robin (2006). Analogue-based Drug Discovery. John Wiley & Sons. [ISBN:9783527607495]
  10. Shorter, Edward (2005). A Historical Dictionary of Psychiatry. Oxford University Press. [ISBN:9780190292010]
  11. Electronic Medicines Compendium: Clonazepam Rosemont 2mg/5ml Oral Solution [Link]
  12. Rivotril (Clonazepam) 0.5 mg and 2 mg Tablets Canadian Product Monograph [File]
  13. Clonazepam Fact Sheet from [File]
  14. Rivotril (Clonazepam) Australian Product Information [File]
External Links
Human Metabolome Database
PubChem Compound
PubChem Substance
Therapeutic Targets Database
RxList Drug Page Drug Page
ATC Codes
N03AE01 — Clonazepam
AHFS Codes
  • 28:12.08 — Benzodiazepines
FDA label
Download (513 KB)
Download (74.3 KB)

Clinical Trials

Clinical Trials
0CompletedTreatmentBurning Mouth Syndrome1
1CompletedNot AvailablePharmacokinetics1
1CompletedNot AvailableTo Determine Bioequivalence Under Fasting Conditions2
1RecruitingTreatmentPain, Neuropathic1
1, 2CompletedBasic SciencePain, Neuropathic1
2CompletedTreatmentREM Sleep Behavior Disorder1
2Not Yet RecruitingTreatmentParkinson's Disease (PD) / REM Sleep Behavior Disorder1
2RecruitingTreatmentCannabis Use Disorders1
2, 3CompletedTreatmentPanic Disorders1
3CompletedTreatmentEpilepsies / Refractory seizure disorders1
3CompletedTreatmentPain NOS1
3CompletedTreatmentStatus; Epilepticus, Tonic-clonic1
3TerminatedTreatmentAnxiety Disorders / Dementias / Depression / Psychosomatic Disorders / Schizophrenic Disorders1
3TerminatedTreatmentEpilepsia Partialis Continua / Epilepsies / Kojewnikov's Epilepsy1
4CompletedTreatmentFear of open spaces / Panic Disorders1
4CompletedTreatmentPost Traumatic Stress Disorder (PTSD)1
4CompletedTreatmentSocial Phobia1
4RecruitingDiagnosticSevere Major Depression Disorder1
4Unknown StatusTreatmentCardiac Arrest1
4WithdrawnTreatmentBurning Mouth Syndrome1
4WithdrawnTreatmentSchizoaffective Disorders / Schizophrenic Disorders / Schizophreniform Disorder1
Not AvailableRecruitingTreatmentREM Sleep Behavior Disorder1


Not Available
  • Actavis Group
  • Aidarex Pharmacuticals LLC
  • Alphapharm Party Ltd.
  • Apotex Inc.
  • Apotheca Inc.
  • A-S Medication Solutions LLC
  • Barr Pharmaceuticals
  • Bryant Ranch Prepack
  • Caraco Pharmaceutical Labs
  • Cardinal Health
  • Caremark LLC
  • Catalent Pharma Solutions
  • Cebert Pharmaceuticals Inc.
  • Centaur Pharmaceuticals Pvt Ltd.
  • Comprehensive Consultant Services Inc.
  • Corepharma LLC
  • Coupler Enterprises Inc.
  • Direct Dispensing Inc.
  • Dispensing Solutions
  • Diversified Healthcare Services Inc.
  • Eon Labs
  • F Hoffmann-La Roche Ltd.
  • Golden State Medical Supply Inc.
  • Goldline Laboratories Inc.
  • H.J. Harkins Co. Inc.
  • Heartland Repack Services LLC
  • Innoviant Pharmacy Inc.
  • Kali Laboratories Inc.
  • Keltman Pharmaceuticals Inc.
  • Lake Erie Medical and Surgical Supply
  • Liberty Pharmaceuticals
  • Major Pharmaceuticals
  • Mckesson Corp.
  • Murfreesboro Pharmaceutical Nursing Supply
  • Mylan
  • Novopharm Ltd.
  • Nucare Pharmaceuticals Inc.
  • Palmetto Pharmaceuticals Inc.
  • Par Pharmaceuticals
  • PD-Rx Pharmaceuticals Inc.
  • Physicians Total Care Inc.
  • Preferred Pharmaceuticals Inc.
  • Prepackage Specialists
  • Prepak Systems Inc.
  • Qualitest
  • Rebel Distributors Corp.
  • Recalcine Laboratorios
  • Redpharm Drug
  • Remedy Repack
  • Sandhills Packaging Inc.
  • Sanofi-Aventis Inc.
  • Southwood Pharmaceuticals
  • St Mary's Medical Park Pharmacy
  • Stat Rx Usa
  • Syntex SA
  • Teva Pharmaceutical Industries Ltd.
  • Torpharm Inc.
  • UDL Laboratories
  • Va Cmop Dallas
  • Vintage Pharmaceuticals Inc.
Dosage forms
TabletOral1.0 mg
TabletOral2.0 mg
TabletOral.5 mg
TabletOral0.5 mg/1
TabletOral1 mg/1
TabletOral2 mg/1
Tablet, orally disintegratingOral.25 mg/1
Tablet, orally disintegratingOral.5 mg/1
Tablet, orally disintegratingOral0.125 mg/1
Tablet, orally disintegratingOral0.25 mg/1
Tablet, orally disintegratingOral0.5 mg/1
Tablet, orally disintegratingOral1 mg/1
Tablet, orally disintegratingOral2 mg/1
TabletOral.5 mg/1
WaferOral0.125 mg/1
WaferOral0.25 mg/1
WaferOral0.5 mg/1
WaferOral1 mg/1
WaferOral2 mg/1
TabletOral0.5 mg
TabletOral1 mg
TabletOral2 mg
TabletOral0.25 mg
Unit descriptionCostUnit
Klonopin 2 mg tablet2.85USD tablet
Klonopin 1 mg tablet2.17USD tablet
Klonopin 0.5 mg tablet1.91USD tablet
ClonazePAM ODT 2 mg Dispersible Tablet1.67USD dispersible tablet
ClonazePAM ODT 0.25 mg Dispersible Tablet1.22USD dispersible tablet
ClonazePAM ODT 0.5 mg Dispersible Tablet1.18USD dispersible tablet
ClonazePAM ODT 0.125 mg Dispersible Tablet1.17USD dispersible tablet
ClonazePAM ODT 1 mg Dispersible Tablet1.1USD dispersible tablet
Clonazepam 2 mg tablet0.81USD tablet
Clonazepam 1 mg tablet0.63USD tablet
Clonazepam 0.5 mg tablet0.61USD tablet
Rivotril 2 mg Tablet0.38USD tablet
Rivotril 0.5 mg Tablet0.22USD tablet
Apo-Clonazepam 2 mg Tablet0.21USD tablet
Co Clonazepam 2 mg Tablet0.21USD tablet
Mylan-Clonazepam 2 mg Tablet0.21USD tablet
Novo-Clonazepam 2 mg Tablet0.21USD tablet
Phl-Clonazepam 2 mg Tablet0.21USD tablet
Pms-Clonazepam 2 mg Tablet0.21USD tablet
Ratio-Clonazepam 2 mg Tablet0.21USD tablet
Sandoz Clonazepam 2 mg Tablet0.21USD tablet
Co Clonazepam 1 mg Tablet0.19USD tablet
Phl-Clonazepam 1 mg Tablet0.19USD tablet
Pms-Clonazepam 1 mg Tablet0.19USD tablet
Sandoz Clonazepam 1 mg Tablet0.19USD tablet
Apo-Clonazepam 0.5 mg Tablet0.12USD tablet
Co Clonazepam 0.5 mg Tablet0.12USD tablet
Mylan-Clonazepam 0.5 mg Tablet0.12USD tablet
Novo-Clonazepam 0.5 mg Tablet0.12USD tablet
Phl-Clonazepam 0.5 mg Tablet0.12USD tablet
Phl-Clonazepam-R 0.5 mg Tablet0.12USD tablet
Pms-Clonazepam 0.5 mg Tablet0.12USD tablet
Pms-Clonazepam-R 0.5 mg Tablet0.12USD tablet
Ratio-Clonazepam 0.5 mg Tablet0.12USD tablet
Sandoz Clonazepam 0.5 mg Tablet0.12USD tablet
Pms-Clonazepam 0.25 mg Tablet0.07USD tablet
DrugBank does not sell nor buy drugs. Pricing information is supplied for informational purposes only.
Not Available


Experimental Properties
melting point (°C)238-240Kariss, J. and Newmark, H.L.; US. Patents 3,116,203; December 31, 1963; and 3,123,529; March 3, 1964; both assigned to Hoffmann-LaRoche, Inc. Keller, O., Steiger, N. and Sternbach, L.H.; U S . Patents 3,121,114; February 11, 1964; and 3,203890; August 31, 1965; both assigned to Hoffmann-LaRoche, Inc. Focella, A. and Rachlin, A.I.; U.S. Patent 3,335,181; August 8, 1967; assigned to Hoffmann- LaRoche. Inc.
water solubility100 mg/L (at 25 °C)MERCK INDEX (1996)
logP2.41HANSCH,C ET AL. (1995)
Predicted Properties
Water Solubility0.0106 mg/mLALOGPS
pKa (Strongest Acidic)11.89ChemAxon
pKa (Strongest Basic)1.86ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count4ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area87.28 Å2ChemAxon
Rotatable Bond Count2ChemAxon
Refractivity84.02 m3·mol-1ChemAxon
Polarizability29.59 Å3ChemAxon
Number of Rings3ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Predicted ADMET features
Human Intestinal Absorption+0.9946
Blood Brain Barrier+0.9718
Caco-2 permeable+0.5313
P-glycoprotein substrateSubstrate0.5594
P-glycoprotein inhibitor INon-inhibitor0.8474
P-glycoprotein inhibitor IINon-inhibitor0.9157
Renal organic cation transporterNon-inhibitor0.8179
CYP450 2C9 substrateNon-substrate0.7777
CYP450 2D6 substrateNon-substrate0.8934
CYP450 3A4 substrateSubstrate0.7295
CYP450 1A2 substrateInhibitor0.7646
CYP450 2C9 inhibitorInhibitor0.5213
CYP450 2D6 inhibitorNon-inhibitor0.8271
CYP450 2C19 inhibitorInhibitor0.7441
CYP450 3A4 inhibitorInhibitor0.5565
CYP450 inhibitory promiscuityHigh CYP Inhibitory Promiscuity0.7255
Ames testNon AMES toxic0.6778
BiodegradationNot ready biodegradable1.0
Rat acute toxicity1.6422 LD50, mol/kg Not applicable
hERG inhibition (predictor I)Weak inhibitor0.9821
hERG inhibition (predictor II)Non-inhibitor0.8734
ADMET data is predicted using admetSAR, a free tool for evaluating chemical ADMET properties. (23092397)


Mass Spec (NIST)
Not Available
SpectrumSpectrum TypeSplash Key
Predicted GC-MS Spectrum - GC-MSPredicted GC-MSNot Available
Mass Spectrum (Electron Ionization)MSsplash10-02a9-2492000000-109e2626e8a128b9e433
Predicted MS/MS Spectrum - 10V, Positive (Annotated)Predicted LC-MS/MSNot Available
Predicted MS/MS Spectrum - 20V, Positive (Annotated)Predicted LC-MS/MSNot Available
Predicted MS/MS Spectrum - 40V, Positive (Annotated)Predicted LC-MS/MSNot Available
Predicted MS/MS Spectrum - 10V, Negative (Annotated)Predicted LC-MS/MSNot Available
Predicted MS/MS Spectrum - 20V, Negative (Annotated)Predicted LC-MS/MSNot Available
Predicted MS/MS Spectrum - 40V, Negative (Annotated)Predicted LC-MS/MSNot Available


This compound belongs to the class of organic compounds known as 1,4-benzodiazepines. These are organic compounds containing a benzene ring fused to a 1,4-azepine.
Organic compounds
Super Class
Organoheterocyclic compounds
Sub Class
Direct Parent
Alternative Parents
Nitroaromatic compounds / Chlorobenzenes / Aryl chlorides / Cyclic carboximidic acids / Ketimines / Propargyl-type 1,3-dipolar organic compounds / Organic oxoazanium compounds / Azacyclic compounds / Organopnictogen compounds / Organooxygen compounds
show 4 more
1,4-benzodiazepine / Nitroaromatic compound / Chlorobenzene / Halobenzene / Aryl chloride / Aryl halide / Monocyclic benzene moiety / Benzenoid / Cyclic carboximidic acid / Ketimine
show 19 more
Molecular Framework
Aromatic heteropolycyclic compounds
External Descriptors
monochlorobenzenes, 1,4-benzodiazepinone (CHEBI:3756)


Protein group
Pharmacological action
Positive allosteric modulator
General Function
Inhibitory extracellular ligand-gated ion channel activity
Specific Function
Component of the heteropentameric receptor for GABA, the major inhibitory neurotransmitter in the vertebrate brain. Functions also as histamine receptor and mediates cellular responses to histamine...

  1. Mohler H, Fritschy JM, Rudolph U: A new benzodiazepine pharmacology. J Pharmacol Exp Ther. 2002 Jan;300(1):2-8. [PubMed:11752090]
  2. Riss J, Cloyd J, Gates J, Collins S: Benzodiazepines in epilepsy: pharmacology and pharmacokinetics. Acta Neurol Scand. 2008 Aug;118(2):69-86. doi: 10.1111/j.1600-0404.2008.01004.x. Epub 2008 Mar 31. [PubMed:18384456]
2. Translocator protein
Pharmacological action
General Function
Cholesterol binding
Specific Function
Can bind protoporphyrin IX and may play a role in the transport of porphyrins and heme (By similarity). Promotes the transport of cholesterol across mitochondrial membranes and may play a role in l...
Gene Name
Uniprot ID
Uniprot Name
Translocator protein
Molecular Weight
18827.81 Da
  1. Carmel I, Fares FA, Leschiner S, Scherubl H, Weisinger G, Gavish M: Peripheral-type benzodiazepine receptors in the regulation of proliferation of MCF-7 human breast carcinoma cell line. Biochem Pharmacol. 1999 Jul 15;58(2):273-8. [PubMed:10423168]
  2. Bono F, Lamarche I, Prabonnaud V, Le Fur G, Herbert JM: Peripheral benzodiazepine receptor agonists exhibit potent antiapoptotic activities. Biochem Biophys Res Commun. 1999 Nov 19;265(2):457-61. [PubMed:10558889]
  3. Bolger GT, Abraham S, Oz N, Weissman BA: Interactions between peripheral-type benzodiazepine receptor ligands and an activator of voltage-operated calcium channels. Can J Physiol Pharmacol. 1990 Jan;68(1):40-5. [PubMed:1691678]
  4. Marano G, Massotti M, Spagnolo A, Carpi A: Enhancement of pharmacologically induced bronchoconstriction by Ro 5-4864. Eur J Pharmacol. 1990 Apr 10;179(1-2):237-40. [PubMed:2364987]
  5. Awad M, Gavish M: Solubilization of peripheral-type benzodiazepine binding sites from cat cerebral cortex. J Neurochem. 1989 Jun;52(6):1880-5. [PubMed:2723642]
  6. Chen X, Ji ZL, Chen YZ: TTD: Therapeutic Target Database. Nucleic Acids Res. 2002 Jan 1;30(1):412-5. [PubMed:11752352]
Pharmacological action
Partial agonist
General Function
Zinc ion binding
Specific Function
Nuclear receptor that binds and is activated by variety of endogenous and xenobiotic compounds. Transcription factor that activates the transcription of multiple genes involved in the metabolism an...
Gene Name
Uniprot ID
Uniprot Name
Nuclear receptor subfamily 1 group I member 2
Molecular Weight
49761.245 Da
  1. Creusot N, Kinani S, Balaguer P, Tapie N, LeMenach K, Maillot-Marechal E, Porcher JM, Budzinski H, Ait-Aissa S: Evaluation of an hPXR reporter gene assay for the detection of aquatic emerging pollutants: screening of chemicals and application to water samples. Anal Bioanal Chem. 2010 Jan;396(2):569-83. doi: 10.1007/s00216-009-3310-y. Epub 2009 Nov 29. [PubMed:20024649]


Pharmacological action
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 react...
Gene Name
Uniprot ID
Uniprot Name
Cytochrome P450 3A4
Molecular Weight
57342.67 Da
  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]
Pharmacological action
General Function
Steroid hydroxylase activity
Specific Function
Metabolizes several precarcinogens, drugs, and solvents to reactive metabolites. Inactivates a number of drugs and xenobiotics and also bioactivates many xenobiotic substrates to their hepatotoxic ...
Gene Name
Uniprot ID
Uniprot Name
Cytochrome P450 2E1
Molecular Weight
56848.42 Da
  1. Tassaneeyakul W, Birkett DJ, Miners JO: Inhibition of human hepatic cytochrome P4502E1 by azole antifungals, CNS-active drugs and non-steroidal anti-inflammatory agents. Xenobiotica. 1998 Mar;28(3):293-301. [PubMed:9574817]
Pharmacological action
General Function
Arylamine n-acetyltransferase activity
Specific Function
Participates in the detoxification of a plethora of hydrazine and arylamine drugs. Catalyzes the N- or O-acetylation of various arylamine and heterocyclic amine substrates and is able to bioactivat...
Gene Name
Uniprot ID
Uniprot Name
Arylamine N-acetyltransferase 2
Molecular Weight
33542.235 Da
  1. Olivera M, Martinez C, Gervasini G, Carrillo JA, Ramos S, Benitez J, Garcia-Martin E, Agundez JA: Effect of common NAT2 variant alleles in the acetylation of the major clonazepam metabolite, 7-aminoclonazepam. Drug Metab Lett. 2007 Jan;1(1):3-5. [PubMed:19356010]
  2. Miller ME, Garland WA, Min BH, Ludwick BT, Ballard RH, Levy RH: Clonazepam acetylation in fast and slow acetylators. Clin Pharmacol Ther. 1981 Sep;30(3):343-7. [PubMed:7273597]


Pharmacological action
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 colloid...
Gene Name
Uniprot ID
Uniprot Name
Serum albumin
Molecular Weight
69365.94 Da
  1. Pacifici GM, Viani A, Rizzo G, Carrai M, Rane A: Plasma protein binding of clonazepam in hepatic and renal insufficiency and after hemodialysis. Ther Drug Monit. 1987 Dec;9(4):369-73. [PubMed:3424402]

Drug created on June 13, 2005 07:24 / Updated on April 18, 2019 06:15