Identification

Name
Guanfacine
Accession Number
DB01018
Description

Guanfacine, or BS 100-141,8,9 is a selective alpha-A2 adrenergic receptor agonist initially indicated for the treatment of hypertension10 but is now indicated as an extended release tablet for the treatment of ADHD.11 Guanfacine was first described in the literature in 1974.9

Guanfacine was granted FDA approval on 27 October 1986.10

Type
Small Molecule
Groups
Approved, Investigational
Structure
Thumb
Weight
Average: 246.093
Monoisotopic: 245.012267339
Chemical Formula
C9H9Cl2N3O
Synonyms
  • Guanfacina
  • Guanfacine
  • Guanfacinum
External IDs
  • SPD 503

Pharmacology

Indication

Guanfacine is indicated alone or as an adjunct with stimulants to treat ADHD.11

Associated Conditions
Contraindications & Blackbox Warnings
Learn about our commercial Contraindications & Blackbox Warnings data.
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Pharmacodynamics

Guanfacine is a selective alpha-2A adrenergic receptor agonist but it is unclear how this translates to the treatment of ADHD.11 It has a long duration of action as it is given once daily and a wide therapeutic window as fatal overdoses have not been described in literature.11 Patients should be counselled regarding the risk of hypotension, bradycardia, and syncope.11

Mechanism of action

Guanfacine is a selective alpha-2A adrenergic receptor agonist, which reduces the effects of the sympathetic nervous system on the heart and circulatory system.11 The link between guanfacine’s molecular mechanism and it’s effect on the treatment of ADHD has not been determined.11

TargetActionsOrganism
AAlpha-2A adrenergic receptor
agonist
Humans
UAlpha-2B adrenergic receptor
binder
Humans
Absorption

Guanfacine is 80% orally bioavailable.1

1mg immediate release oral guanfacine reaches a Cmax of 2.5±0.6ng/mL with a Tmax of 3.0h and an AUC of 56±15ng*h/mL.11 1mg extended release oral guanfacine reaches a Cmax of 1.0±0.3ng/mL with a Tmax of 6.0h and an AUC of 32±9ng*h/mL.11

In adults, a 4mg oral extended release dose reaches a Cmax of 3.58±1.39ng/mL with a Tmax of 5.5h; in children, a 2mg oral extended relsease dose reaches a Cmax of 2.6±1.03ng/mL with a Tmax of 4.98h; in adolescents, a 2mg oral extended release dose reaches a Cmax of 1.7±0.43ng/mL with a Tmax of 4.96h.7

Volume of distribution

Guanfacine has a volume of distribution of 6.3L/kg.1

Protein binding

Guanfacine is approximately 70% protein bound in serum.1,11

Metabolism

Guanfacine is oxidized by CYP3A46 to it's main metabolite, 3-hydroxyguanfacine.4 3-hydroxyguanfacine is then either glucuronidated or sulphated.4,5

Hover over products below to view reaction partners

Route of elimination

Guanfacine is 57.0±32.0% eliminated in the urine in patients with normal renal function.2 Patients with a glomerular filtration rate (GFR) of 10-30mL/min eliminate 14.0±9.0% of a dose in the urine, while patients with a GFR of <1mL/min eliminate 7.5±2.4% of a dose in the urine.2

Half-life

Guanfacine has a half life of 17 hours, but this may range from 10-30 hours.1 The half life is largely independant of renal function.2

Clearance

Guanfacine has a total body cleraance of 360±262mL/min and a renal clearance of 233±245mL/min in patients with normal renal function. Patients with a glomerular filtration rate (GFR) of 10-30mL/min had a total body clearance of 308±274mL/min and a renal clearance of 34±22mL/min.2 Patients with a GFR of <1mL/min had a total body clearance of 257±187mL/min and a renal clearance of 18±15mL/min.2

Adverse Effects
Learn about our commercial Adverse Effects data.
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Toxicity

The oral LD50 in rats is 142mg/kg and 15.3mg/kg in mice.12 The subcutaneous LD50 in rats is 114mg/kg and 46mg/kg in mice.12

Patients experiencing and overdose may present with hypotension, drowsiness, lethargy, and bradycardia.11 Overdose should be managed by first calling local poison control. Patients may require intravenous saline to maintain blood pressure.3

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

Interactions

Drug Interactions
This information should not be interpreted without the help of a healthcare provider. If you believe you are experiencing an interaction, contact a healthcare provider immediately. The absence of an interaction does not necessarily mean no interactions exist.
DrugInteraction
AbacavirGuanfacine may decrease the excretion rate of Abacavir which could result in a higher serum level.
AbametapirThe serum concentration of Guanfacine can be increased when it is combined with Abametapir.
AcarboseAcarbose may decrease the excretion rate of Guanfacine which could result in a higher serum level.
AcebutololThe therapeutic efficacy of Guanfacine can be decreased when used in combination with Acebutolol.
AceclofenacThe therapeutic efficacy of Guanfacine can be decreased when used in combination with Aceclofenac.
AcemetacinThe therapeutic efficacy of Guanfacine can be decreased when used in combination with Acemetacin.
AcetaminophenAcetaminophen may decrease the excretion rate of Guanfacine which could result in a higher serum level.
AcetazolamideThe risk or severity of adverse effects can be increased when Acetazolamide is combined with Guanfacine.
AcetophenazineThe risk or severity of adverse effects can be increased when Guanfacine is combined with Acetophenazine.
AcetylcholineThe risk or severity of adverse effects can be increased when Guanfacine is combined with Acetylcholine.
Additional Data Available
  • Extended Description
    Extended Description

    Extended description of the mechanism of action and particular properties of each drug interaction.

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  • Severity
    Severity

    A severity rating for each drug interaction, from minor to major.

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  • Evidence Level
    Evidence Level

    A rating for the strength of the evidence supporting each drug interaction.

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  • Action
    Action

    An effect category for each drug interaction. Know how this interaction affects the subject drug.

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Food Interactions
  • Avoid alcohol.
  • Do not take with or immediately after a high-fat meal. High fat meals increase drug exposure.

Products

Product Ingredients
IngredientUNIICASInChI Key
Guanfacine hydrochloridePML56A160O29110-48-3DGFYECXYGUIODH-UHFFFAOYSA-N
Product Images
International/Other Brands
Estulic (Egis)
Brand Name Prescription Products
NameDosageStrengthRouteLabellerMarketing StartMarketing EndRegionImage
IntunivTablet, extended release2 mg/1OralTYA Pharmaceuticals2009-09-02Not applicableUs64725 051520180907 15195 1kpsb6y
IntunivTablet, extended release3 mgOralShire2015-09-17Not applicableEu
IntunivTablet, extended release4 mgOralShire2015-09-17Not applicableEu
IntunivTablet, extended release2 mg/1OralShire US Manufacturing Inc.2009-09-02Not applicableUs54092 0515 02 nlmimage10 071603e0
IntunivTablet, extended release1 mgOralShire2015-09-17Not applicableEu
IntunivTablet, extended release4 mgOralShire2015-09-17Not applicableEu
IntunivTablet, extended release2 mgOralShire2015-09-17Not applicableEu
IntunivTablet, extended release1 mg/1OralShire US Manufacturing Inc.2009-09-02Not applicableUs54092 0513 02 nlmimage10 011600e0
IntunivTablet, extended release4 mg/1OralShire US Manufacturing Inc.2009-09-02Not applicableUs54092 0519 02 nlmimage10 fd15feaf
IntunivTablet, extended release2 mgOralShire2015-09-17Not applicableEu
Additional Data Available
  • Application Number
    Application Number

    A unique ID assigned by the FDA when a product is submitted for approval by the labeller.

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  • Product Code
    Product Code

    A governmentally-recognized ID which uniquely identifies the product within its regulatory market.

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Generic Prescription Products
NameDosageStrengthRouteLabellerMarketing StartMarketing EndRegionImage
GuanfacineTablet2 mg/1OralGolden State Medical Supply2014-04-222017-02-28Us
GuanfacineTablet2 mg/1OralEpic Pharma, LLC2013-12-02Not applicableUs
GuanfacineTablet2 mg/1OralGenpharm Ulc2015-11-012015-11-30Us
GuanfacineTablet2 mg/1OralEpic Pharma, LLC2013-12-022019-05-22Us
GuanfacineTablet, extended release2 mg/1Oralbryant ranch prepack2014-12-01Not applicableUs
GuanfacineTablet1 mg/1OralActavis Pharma Company1995-10-17Not applicableUs00591 0444 01 nlmimage10 7807bc0d
GuanfacineTablet2 mg/1OralMylan Pharmaceuticals Inc.1997-01-27Not applicableUs00378 1190 01 nlmimage10 8b3b459a
GuanfacineTablet, extended release2 mg/1Oralbryant ranch prepack2018-08-17Not applicableUs
GuanfacineTablet2 mg/1OralREMEDYREPACK INC.2018-08-14Not applicableUs
GuanfacineTablet1 mg/1OralPuraCap Laboratories LLC dba Blu Pharmaceuticals2016-11-14Not applicableUs
Additional Data Available
  • Application Number
    Application Number

    A unique ID assigned by the FDA when a product is submitted for approval by the labeller.

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  • Product Code
    Product Code

    A governmentally-recognized ID which uniquely identifies the product within its regulatory market.

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Mixture Products
NameIngredientsDosageRouteLabellerMarketing StartMarketing EndRegionImage
IntunivGuanfacine hydrochloride (1 mg/1) + Guanfacine hydrochloride (2 mg/1)KitOralShire US Manufacturing Inc.2009-09-022011-06-15Us
IntunivGuanfacine hydrochloride (1 mg/1) + Guanfacine hydrochloride (2 mg/1)OralShire US Manufacturing Inc.2009-09-02Not applicableUs
IntunivGuanfacine hydrochloride (1 mg/1) + Guanfacine hydrochloride (2 mg/1)KitOralShire US Manufacturing Inc.2009-09-022011-06-15Us
IntunivGuanfacine hydrochloride (1 mg/1) + Guanfacine hydrochloride (2 mg/1)OralShire US Manufacturing Inc.2009-09-02Not applicableUs

Categories

ATC Codes
C02AC02 — Guanfacine
Drug Categories
Chemical TaxonomyProvided by Classyfire
Description
This compound belongs to the class of organic compounds known as dichlorobenzenes. These are compounds containing a benzene with exactly two chlorine atoms attached to it.
Kingdom
Organic compounds
Super Class
Benzenoids
Class
Benzene and substituted derivatives
Sub Class
Halobenzenes
Direct Parent
Dichlorobenzenes
Alternative Parents
Aryl chlorides / Propargyl-type 1,3-dipolar organic compounds / Carboximidamides / Organopnictogen compounds / Organooxygen compounds / Organochlorides / Imines / Hydrocarbon derivatives
Substituents
1,3-dichlorobenzene / Aromatic homomonocyclic compound / Aryl chloride / Aryl halide / Carboximidamide / Hydrocarbon derivative / Imine / Organic 1,3-dipolar compound / Organic nitrogen compound / Organic oxygen compound
Molecular Framework
Aromatic homomonocyclic compounds
External Descriptors
acetamides (CHEBI:5558)

Chemical Identifiers

UNII
30OMY4G3MK
CAS number
29110-47-2
InChI Key
INJOMKTZOLKMBF-UHFFFAOYSA-N
InChI
InChI=1S/C9H9Cl2N3O/c10-6-2-1-3-7(11)5(6)4-8(15)14-9(12)13/h1-3H,4H2,(H4,12,13,14,15)
IUPAC Name
N-carbamimidoyl-2-(2,6-dichlorophenyl)acetamide
SMILES
NC(=N)NC(=O)CC1=C(Cl)C=CC=C1Cl

References

Synthesis Reference

U.S. Patent 3,632,645.

General References
  1. Cruz MP: Guanfacine Extended-Release Tablets (Intuniv), a Nonstimulant Selective Alpha(2A)-Adrenergic Receptor Agonist For Attention-Deficit/Hyperactivity Disorder. P T. 2010 Aug;35(8):448-51. [PubMed:20844694]
  2. Kirch W, Kohler H, Braun W: Elimination of guanfacine in patients with normal and impaired renal function. Br J Clin Pharmacol. 1980;10 Suppl 1:33S-35S. doi: 10.1111/j.1365-2125.1980.tb04902.x. [PubMed:6994776]
  3. Minns AB, Clark RF, Schneir A: Guanfacine overdose resulting in initial hypertension and subsequent delayed, persistent orthostatic hypotension. Clin Toxicol (Phila). 2010 Feb;48(2):146-8. doi: 10.3109/15563650903505174. [PubMed:20136479]
  4. Kiechel JR: Pharmacokinetics and metabolism of guanfacine in man: a review. Br J Clin Pharmacol. 1980;10 Suppl 1:25S-32S. doi: 10.1111/j.1365-2125.1980.tb04901.x. [PubMed:6994775]
  5. Guerret M, Julien-Larose C, Kiechel JR, Lavene D: Determination of 3-hydroxy-guanfacine in biological fluids by electron-capture gas-liquid chromatography. J Chromatogr. 1982 Dec 10;233:181-92. doi: 10.1016/s0378-4347(00)81745-4. [PubMed:6761349]
  6. Inoue Y, Morita H, Nozawa K, Kanazu T: Metabolite profiling of guanfacine in plasma and urine of healthy Japanese subjects after oral administration of guanfacine extended-release tablets. Biopharm Drug Dispos. 2019 Sep;40(8):282-293. doi: 10.1002/bdd.2201. Epub 2019 Aug 7. [PubMed:31313320]
  7. Martin P, Satin L, Vince BD, Padilla AF, White C, Corcoran M, Stevenson A, Ermer J: Pharmacokinetics and pharmacodynamics of guanfacine extended release in adolescents aged 13-17 years with attention-deficit/hyperactivity disorder. Clin Pharmacol Drug Dev. 2014 Jul;3(4):252-61. doi: 10.1002/cpdd.124. Epub 2014 May 17. [PubMed:27128830]
  8. Dubach UC, Huwyler R, Radielovic P, Singeisen M: A new centrally action antihypertensive agent guanfacine (BS 100-141). Arzneimittelforschung. 1977;27(3):674-6. [PubMed:326262]
  9. Scholtysik G: Proceedings: Inhibition of effects of accelerator nerve stimulation in cats and rabbits by BS 100-141 and guanabenz. Naunyn Schmiedebergs Arch Pharmacol. 1974;282(Suppl):suppl 282:R86. [PubMed:4276642]
  10. FDA Approved Drug Products: Tenex Guanfacine Hydrochloride Oral Tablets (Discontinued) [Link]
  11. FDA Approved Drug Products: Intuniv Guanfacine Hydrochloride Extended Release Oral Tablets [Link]
  12. Cayman Chemical: Guanfacine MSDS [Link]
Human Metabolome Database
HMDB0015153
KEGG Drug
D08031
KEGG Compound
C07037
PubChem Compound
3519
PubChem Substance
46506169
ChemSpider
3399
BindingDB
81984
RxNav
40114
ChEBI
5558
ChEMBL
CHEMBL862
ZINC
ZINC000003872738
Therapeutic Targets Database
DAP000900
PharmGKB
PA449825
Guide to Pharmacology
GtP Drug Page
RxList
RxList Drug Page
Drugs.com
Drugs.com Drug Page
PDRhealth
PDRhealth Drug Page
Wikipedia
Guanfacine
AHFS Codes
  • 24:08.16 — Central Alpha-agonists

Clinical Trials

Clinical Trials
PhaseStatusPurposeConditionsCount
4Active Not RecruitingTreatmentObstructive Sleep Apnea (OSA)1
4CompletedBasic ScienceAttention Deficit Hyperactivity Disorder (ADHD) / Attention Deficit/Hyperactivity Disorder1
4CompletedTreatmentAdult Attention Deficit Hyperactivity Disorder (ADHD)1
4CompletedTreatmentAttention Deficit Disorder With Hyperactivity2
4CompletedTreatmentAttention Deficit Hyperactivity Disorder (ADHD) / Attention Deficit/Hyperactivity Disorder2
4CompletedTreatmentAttention Deficit Hyperactivity Disorder (ADHD) / Attention Deficit/Hyperactivity Disorder / Deficient Emotional Self-Regulation (DESR)1
4CompletedTreatmentAttention Deficit Hyperactivity Disorder (ADHD) / Attention Deficit/Hyperactivity Disorder / Reading Disability1
4CompletedTreatmentAttention Deficit Hyperactivity Disorder (ADHD) / Childhood Aggression / Intermittent Explosive Disorder / Oppositional Defiant Disorder1
4CompletedTreatmentAttention Deficit/Hyperactivity Disorder / Attention-Deficit/Hyperactivity Disorder1
4CompletedTreatmentGilles de la Tourette's Syndrome / Tourette's Disorder (TD)1

Pharmacoeconomics

Manufacturers
  • Shire development inc
  • Amneal pharmaceutical
  • Mikah pharma llc
  • Mylan pharmaceuticals inc
  • Watson laboratories inc
  • Promius pharma llc
Packagers
  • Actavis Group
  • Advanced Pharmaceutical Services Inc.
  • Amerisource Health Services Corp.
  • Amneal Pharmaceuticals
  • Atlantic Biologicals Corporation
  • Cardinal Health
  • Industriale Chimica S.R.L.
  • Major Pharmaceuticals
  • Murfreesboro Pharmaceutical Nursing Supply
  • Mylan
  • Par Pharmaceuticals
  • Patheon Inc.
  • Pharmaceutical Utilization Management Program VA Inc.
  • Pharmedix
  • Physicians Total Care Inc.
  • Promius Pharma
  • Qualitest
  • Resource Optimization and Innovation LLC
  • Shire Inc.
  • Southwood Pharmaceuticals
  • Watson Pharmaceuticals
Dosage Forms
FormRouteStrength
Tablet, extended releaseOral3 mg/1
Tablet, extended releaseOral4 mg/1
TabletOral1 mg/1
TabletOral2 mg/1
Tablet, film coated, extended releaseOral1 mg/1
Tablet, film coated, extended releaseOral2 mg/1
Tablet, film coated, extended releaseOral3 mg/1
Tablet, film coated, extended releaseOral4 mg/1
KitOral
Tablet, extended releaseOral1 mg/1
Tablet, extended releaseOral1 mg
Tablet, extended releaseOral2 mg/1
Tablet, extended releaseOral2 mg
Tablet, extended releaseOral3 mg
Tablet, extended releaseOral4 mg
Tablet, extended releaseOral
Prices
Unit descriptionCostUnit
Intuniv 1 mg 24 Hour tablet5.72USD tablet
Intuniv 2 mg 24 Hour tablet5.72USD tablet
Intuniv 3 mg 24 Hour tablet5.72USD tablet
Intuniv 4 mg 24 Hour tablet5.72USD tablet
Intuniv er 1 mg tablet5.5USD tablet
Intuniv er 2 mg tablet5.5USD tablet
Intuniv er 3 mg tablet5.5USD tablet
Intuniv er 4 mg tablet5.5USD tablet
Tenex 2 mg tablet4.3USD tablet
Tenex 1 mg tablet2.9USD tablet
Guanfacine HCl 2 mg tablet1.22USD tablet
Guanfacine 2 mg tablet1.18USD tablet
Guanfacine HCl 1 mg tablet0.91USD tablet
Guanfacine 1 mg tablet0.87USD tablet
DrugBank does not sell nor buy drugs. Pricing information is supplied for informational purposes only.
Patents
Patent NumberPediatric ExtensionApprovedExpires (estimated)Region
US5854290Yes1998-12-292016-03-21Us
US6811794Yes2004-11-022023-01-04Us
US6287599Yes2001-09-112021-06-20Us
Additional Data Available
  • Filed On
    Filed On

    The date on which a patent was filed with the relevant government.

    Learn more

Properties

State
Solid
Experimental Properties
PropertyValueSource
melting point (°C)213-216U.S. Patent 3,632,645.
water solubility1mg/mLFDA Label
logP0.857ChemSpider
Predicted Properties
PropertyValueSource
Water Solubility0.139 mg/mLALOGPS
logP2.28ALOGPS
logP1.74ChemAxon
logS-3.2ALOGPS
pKa (Strongest Acidic)12.94ChemAxon
pKa (Strongest Basic)6.65ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count3ChemAxon
Polar Surface Area78.97 Å2ChemAxon
Rotatable Bond Count2ChemAxon
Refractivity69.63 m3·mol-1ChemAxon
Polarizability21.75 Å3ChemAxon
Number of Rings1ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Predicted ADMET Features
PropertyValueProbability
Human Intestinal Absorption+0.9313
Blood Brain Barrier+0.9567
Caco-2 permeable-0.5101
P-glycoprotein substrateNon-substrate0.6778
P-glycoprotein inhibitor INon-inhibitor0.8782
P-glycoprotein inhibitor IINon-inhibitor0.9833
Renal organic cation transporterNon-inhibitor0.6443
CYP450 2C9 substrateNon-substrate0.7572
CYP450 2D6 substrateNon-substrate0.7948
CYP450 3A4 substrateNon-substrate0.6475
CYP450 1A2 substrateNon-inhibitor0.9046
CYP450 2C9 inhibitorNon-inhibitor0.8893
CYP450 2D6 inhibitorInhibitor0.8931
CYP450 2C19 inhibitorNon-inhibitor0.7376
CYP450 3A4 inhibitorNon-inhibitor0.831
CYP450 inhibitory promiscuityLow CYP Inhibitory Promiscuity0.6619
Ames testNon AMES toxic0.7223
CarcinogenicityNon-carcinogens0.8107
BiodegradationNot ready biodegradable0.9843
Rat acute toxicity2.7408 LD50, mol/kg Not applicable
hERG inhibition (predictor I)Weak inhibitor0.9677
hERG inhibition (predictor II)Non-inhibitor0.9285
ADMET data is predicted using admetSAR, a free tool for evaluating chemical ADMET properties. (23092397)

Spectra

Mass Spec (NIST)
Not Available
Spectra
SpectrumSpectrum TypeSplash Key
Predicted GC-MS Spectrum - GC-MSPredicted GC-MSNot Available
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

Targets

Kind
Protein
Organism
Humans
Pharmacological action
Yes
Actions
Agonist
General Function
Thioesterase binding
Specific Function
Alpha-2 adrenergic receptors mediate the catecholamine-induced inhibition of adenylate cyclase through the action of G proteins. The rank order of potency for agonists of this receptor is oxymetazo...
Gene Name
ADRA2A
Uniprot ID
P08913
Uniprot Name
Alpha-2A adrenergic receptor
Molecular Weight
48956.275 Da
References
  1. Avery RA, Franowicz JS, Studholme C, van Dyck CH, Arnsten AF: The alpha-2A-adrenoceptor agonist, guanfacine, increases regional cerebral blood flow in dorsolateral prefrontal cortex of monkeys performing a spatial working memory task. Neuropsychopharmacology. 2000 Sep;23(3):240-9. [PubMed:10942848]
  2. Sagvolden T: The alpha-2A adrenoceptor agonist guanfacine improves sustained attention and reduces overactivity and impulsiveness in an animal model of Attention-Deficit/Hyperactivity Disorder (ADHD). Behav Brain Funct. 2006 Dec 15;2:41. [PubMed:17173664]
  3. Yuan R, Wu Z, Kostenyuk IA, Burns JK: G-protein-coupled alpha2A-adrenoreceptor agonists differentially alter citrus leaf and fruit abscission by affecting expression of ACC synthase and ACC oxidase. J Exp Bot. 2005 Jul;56(417):1867-75. Epub 2005 May 31. [PubMed:15928018]
  4. Birnbaum SG, Podell DM, Arnsten AF: Noradrenergic alpha-2 receptor agonists reverse working memory deficits induced by the anxiogenic drug, FG7142, in rats. Pharmacol Biochem Behav. 2000 Nov;67(3):397-403. [PubMed:11164065]
  5. Millan MJ: Evidence that an alpha 2A-adrenoceptor subtype mediates antinociception in mice. Eur J Pharmacol. 1992 May 14;215(2-3):355-6. [PubMed:1356794]
  6. Stahl SM: Mechanism of action of alpha 2A-adrenergic agonists in attention-deficit/hyperactivity disorder with or without oppositional symptoms. J Clin Psychiatry. 2010 Mar;71(3):223-4. doi: 10.4088/JCP.09bs05899pur. [PubMed:20331927]
  7. FDA Approved Drug Products: Intuniv Guanfacine Hydrochloride Extended Release Oral Tablets [Link]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Binder
Curator comments
Guanfacine binds to Alpha-2B adrenergic receptors with such low affinity that it is not clinically relevant.
General Function
Epinephrine binding
Specific Function
Alpha-2 adrenergic receptors mediate the catecholamine-induced inhibition of adenylate cyclase through the action of G proteins. The rank order of potency for agonists of this receptor is clonidine...
Gene Name
ADRA2B
Uniprot ID
P18089
Uniprot Name
Alpha-2B adrenergic receptor
Molecular Weight
49565.8 Da
References
  1. Uhlen S, Wikberg JE: Delineation of rat kidney alpha 2A- and alpha 2B-adrenoceptors with [3H]RX821002 radioligand binding: computer modelling reveals that guanfacine is an alpha 2A-selective compound. Eur J Pharmacol. 1991 Sep 17;202(2):235-43. [PubMed:1666366]

Enzymes

Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
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
CYP3A4
Uniprot ID
P08684
Uniprot Name
Cytochrome P450 3A4
Molecular Weight
57342.67 Da
References
  1. Clement B, Demesmaeker M: Microsomal catalyzed N-hydroxylation of guanfacine and reduction of N-hydroxyguanfacine. Arch Pharm (Weinheim). 1997 Oct;330(9-10):303-6. [PubMed:9396389]
  2. Guillouzo A, Le Bigot JF, Guguen-Guillouzo C, Kiechel JR: Presence of phase I and phase II drug metabolizing enzymes in cultured human foetal hepatocytes. Biochem Pharmacol. 1982 Jul 15;31(14):2427-30. [PubMed:6751332]
  3. FDA Approved Drug Products: Intuniv Guanfacine Hydrochloride Extended Release Oral Tablets [Link]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
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 im...
Gene Name
CYP2C19
Uniprot ID
P33261
Uniprot Name
Cytochrome P450 2C19
Molecular Weight
55930.545 Da
References
  1. Clement B, Demesmaeker M: Microsomal catalyzed N-hydroxylation of guanfacine and reduction of N-hydroxyguanfacine. Arch Pharm (Weinheim). 1997 Oct;330(9-10):303-6. [PubMed:9396389]
  2. Guillouzo A, Le Bigot JF, Guguen-Guillouzo C, Kiechel JR: Presence of phase I and phase II drug metabolizing enzymes in cultured human foetal hepatocytes. Biochem Pharmacol. 1982 Jul 15;31(14):2427-30. [PubMed:6751332]

Transporters

Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Inhibitor
General Function
Monovalent cation:proton antiporter activity
Specific Function
Solute transporter for tetraethylammonium (TEA), 1-methyl-4-phenylpyridinium (MPP), cimetidine, N-methylnicotinamide (NMN), metformin, creatinine, guanidine, procainamide, topotecan, estrone sulfat...
Gene Name
SLC47A1
Uniprot ID
Q96FL8
Uniprot Name
Multidrug and toxin extrusion protein 1
Molecular Weight
61921.585 Da
References
  1. FDA Approved Drug Products: Intuniv Guanfacine Hydrochloride Extended Release Oral Tablets [Link]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
Inhibitor
General Function
Secondary active organic cation transmembrane transporter activity
Specific Function
Translocates a broad array of organic cations with various structures and molecular weights including the model compounds 1-methyl-4-phenylpyridinium (MPP), tetraethylammonium (TEA), N-1-methylnico...
Gene Name
SLC22A1
Uniprot ID
O15245
Uniprot Name
Solute carrier family 22 member 1
Molecular Weight
61153.345 Da
References
  1. FDA Approved Drug Products: Intuniv Guanfacine Hydrochloride Extended Release Oral Tablets [Link]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
General Function
Quaternary ammonium group transmembrane transporter activity
Specific Function
Mediates tubular uptake of organic compounds from circulation. Mediates the influx of agmatine, dopamine, noradrenaline (norepinephrine), serotonin, choline, famotidine, ranitidine, histamin, creat...
Gene Name
SLC22A2
Uniprot ID
O15244
Uniprot Name
Solute carrier family 22 member 2
Molecular Weight
62579.99 Da
References
  1. FDA Approved Drug Products: Intuniv Guanfacine Hydrochloride Extended Release Oral Tablets [Link]

Drug created on June 13, 2005 07:24 / Updated on August 12, 2020 21:57

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