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Identification
Name Doxepin
Accession Number DB01142 (APRD00398)
Type small molecule
Groups approved
Description

Doxepin hydrochloride is a dibenzoxepin-derivative tricyclic antidepressant (TCA). TCAs are structurally similar to phenothiazines. They contain a tricyclic ring system with an alkyl amine substituent on the central ring. In non-depressed individuals, doxepin does not affect mood or arousal, but may cause sedation. In depressed individuals, doxepin exerts a positive effect on mood. TCAs are potent inhibitors of serotonin and norepinephrine reuptake. Tertiary amine TCAs, such as doxepin and amitriptyline, are more potent inhibitors of serotonin reuptake than secondary amine TCAs, such as nortriptyline and desipramine. TCAs also down-regulate cerebral cortical β-adrenergic receptors and sensitize post-synaptic serotonergic receptors with chronic use. The antidepressant effects of TCAs are thought to be due to an overall increase in serotonergic neurotransmission. TCAs also block histamine H1 receptors, α1-adrenergic receptors and muscarinic receptors, which accounts for their sedative, hypotensive and anticholinergic effects (e.g. blurred vision, dry mouth, constipation, urinary retention), respectively. Doxepin has less sedative and anticholinergic effects than amitriptyline. See toxicity section below for a complete listing of side effects. Doxepin may be used to treat depression and insomnia. Unlabeled indications include chronic and neuropathic pain, and anxiety. Doxepin may also be used as a second line agent to treat idiopathic urticaria.
Structure Thumb
Download: MOL | SDF | SMILES | InChI
Display: 2D Structure | 3D Structure
Synonyms
  • Doxepin Hcl
  • Doxepin, Hydrochloride
  • Doxepina [INN-Spanish]
  • Doxepine
  • Doxepinum [INN-Latin]
Brand names
  • Adapin
  • Aponal
  • Curatin
  • Quitaxon
  • Sinequan (Pfizer)
  • Triadapin
  • Zonalon
Brand name mixtures Not Available
Categories
  • Antidepressants
  • Anti-anxiety Agents
  • Antipruritics
  • Antidepressive Agents, Tricyclic
  • Norepinephrine-Reuptake Inhibitors
  • Histamine Antagonists
CAS number 1668-19-5
Weight Average: 279.3761
Monoisotopic: 279.162314299
Chemical Formula C19H21NO
InChI Key InChIKey=ODQWQRRAPPTVAG-GZTJUZNOSA-N
InChI
InChI=1S/C19H21NO/c1-20(2)13-7-11-17-16-9-4-3-8-15(16)14-21-19-12-6-5-10-18(17)19/h3-6,8-12H,7,13-14H2,1-2H3/b17-11+
Plain Text
IUPAC Name
dimethyl({3-[(2E)-9-oxatricyclo[9.4.0.0^{3,8}]pentadeca-1(11),3(8),4,6,12,14-hexaen-2-ylidene]propyl})amine
SMILES
CN(C)CC\C=C1/C2=C(COC3=C1C=CC=C3)C=CC=C2
Plain Text
Mass Spec Not Available
Taxonomy
Kingdom Organic
Classes
  • Benzyl Alcohols and Derivatives
  • Phenols and Derivatives
  • Phenylpropenes
  • Ethers
  • Anisoles
Substructures
  • Alkanes and Alkenes
  • Benzyl Alcohols and Derivatives
  • Phenols and Derivatives
  • Phenylpropenes
  • Ethers
  • Benzene and Derivatives
  • Aliphatic and Aryl Amines
  • Isoprenes
  • Heterocyclic compounds
  • Aromatic compounds
  • Anisoles
  • Phenyl Esters
Pharmacology
Indication Labeled indications: depression and insomnia. Unlabeled indications: chronic and neuropathic pain, anxiety, idiopathic urticaria.
Pharmacodynamics Doxepin, a tricyclic antidepressant of the dibenzoxepin type, is used to treat depression and anxiety and, topically, pruritus associated with eczema. Doxepin has substantial anticholinergic and sedative effects.
Mechanism of action The mechanism of action of doxepin is not completely understood. It is thought that Like amitriptyline, doxepin enhances the actions of norepinephrine and serotonin by blocking their reuptake at the neuronal membrane. Doxepin may also act on histamine H1-receptors, resulting in sedative effects, and β-adrenergic receptors.
Absorption Well-absorbed from the GI tract. Peak plasma concentrations occur within 2 hours of oral administration.
Volume of distribution Not Available
Protein binding Highly bound to plasma proteins.
Metabolism

Extensively metabolized in the liver via the same pathways as other TCAs. N-demethylation produces an active metabolite, N-desmethyldoxepin.

Enzyme Metabolite Reaction Km Vmax
Cytochrome P450 2D6 N-desmethyldoxepin N-demethylation 12.7 12.36
Route of elimination Not Available
Half life 6 - 24.5 hours
Clearance Not Available
Toxicity LD50=26 (mg/kg) (in mice, iv); LD50=16 (mg/kg) (in rats, iv); Cardiac dysrhythmias, severe hypotension, convulsions, and CNS depression, including coma. Changes in the electrocardiogram, particularly in QRS axis or width, are clinically significant indicators of tricyclic antidepressant toxicity. Side effects include: sedation, hypotension, blurred vision, dry mouth, constipation, urinary retention, postural hypotension, tachycardia, hypertension, ECG changes, heart failure, impaired memory and delirium, and precipitation of hypomanic or manic episodes in bipolar depression. Withdrawal symptoms include gastrointestinal disturbances, anxiety, and insomnia.
Affected organisms
  • Humans and other mammals
Pathways Not Available
Pharmacoeconomics
Manufacturers
  • Clonmel healthcare ltd
  • Mutual pharmaceutical co inc
  • Mylan pharmaceuticals inc
  • New river pharmaceuticals inc
  • Par pharmaceutical inc
  • Purepac pharmaceutical co
  • Quantum pharmics ltd
  • Sandoz inc
  • Watson laboratories inc
  • Pharmaceutical assoc inc
  • Silarx pharmaceuticals inc
  • Teva pharmaceuticals usa
  • Wockhardt eu operations (swiss) ag
  • Nycomed us inc
  • Pfizer Inc
Packagers
Dosage forms
Form Route Strength
Capsule Oral 10 mg
Capsule Oral 100 mg
Capsule Oral 150 mg
Capsule Oral 25 mg
Capsule Oral 50 mg
Capsule Oral 75 mg
Solution Oral 10 mg/ml
Prices
Unit description Cost Unit
Zonalon 5% Cream 45 gm Tube 190.13 USD tube
Zonalon 5% Cream 30 gm Tube 144.29 USD tube
Doxepin hcl powder 8.88 USD g
Doxepin 150 mg capsule 3.33 USD capsule
Prudoxin 5% cream 3.05 USD g
Sinequan 100 mg Capsule 1.22 USD capsule
Novo-Doxepin 150 mg Capsule 1.18 USD capsule
Sinequan 75 mg Capsule 0.93 USD capsule
Zonalon 5% cream 0.89 USD g
Doxepin HCl 150 mg capsule 0.87 USD capsule
Apo-Doxepin 100 mg Capsule 0.68 USD capsule
Novo-Doxepin 100 mg Capsule 0.68 USD capsule
Sinequan 50 mg Capsule 0.64 USD capsule
Doxepin 50 mg capsule 0.57 USD capsule
Doxepin HCl 100 mg capsule 0.56 USD capsule
Novo-Doxepin 75 mg Capsule 0.52 USD capsule
Apo-Doxepin 75 mg Capsule 0.52 USD capsule
Doxepin HCl 75 mg capsule 0.43 USD capsule
Apo-Doxepin 50 mg Capsule 0.36 USD capsule
Novo-Doxepin 50 mg Capsule 0.36 USD capsule
Sinequan 25 mg Capsule 0.35 USD capsule
Doxepin 10 mg capsule 0.32 USD capsule
Sinequan 10 mg Capsule 0.28 USD capsule
Doxepin HCl 50 mg capsule 0.25 USD capsule
Doxepin HCl 25 mg capsule 0.23 USD capsule
Doxepin 75 mg capsule 0.21 USD capsule
Doxepin HCl 10 mg capsule 0.21 USD capsule
Apo-Doxepin 10 mg Capsule 0.2 USD capsule
Apo-Doxepin 25 mg Capsule 0.19 USD capsule
Novo-Doxepin 25 mg Capsule 0.19 USD capsule
Doxepin 25 mg capsule 0.18 USD capsule
Doxepin 100 mg capsule 0.14 USD capsule
Doxepin HCl 10 mg/ml Concentrate 0.13 USD ml
Patents Not Available
Properties
State solid
Melting point 184-186 oC
Experimental Properties
Property Value Source
water solubility 4.9 mg/L PhysProp
logP 4 PhysProp
logS -3.4 [ADME Research, USCD] PhysProp
Predicted Properties
Property Value Source
water solubility 3.19e-02 g/l ALOGPS
logP 4.08 ALOGPS
logP 3.84 ChemAxon Molconvert
logS -3.94 ALOGPS
pKa ChemAxon Molconvert
hydrogen acceptor count 2 ChemAxon Molconvert
hydrogen donor count 0 ChemAxon Molconvert
polar surface area 12.47 ChemAxon Molconvert
rotatable bond count 3 ChemAxon Molconvert
refractivity 98.24 ChemAxon Molconvert
polarizability 32.53 ChemAxon Molconvert
References
Synthesis Reference Not Available
General Reference Not Available
External Links
Resource Link
KEGG Compound C06971 Link_out
PubChem Compound 667477 Link_out
PubChem Substance 46505232 Link_out
ChemSpider 580858 Link_out
ChEBI 4710 Link_out
ChEMBL 4710 Link_out
Therapeutic Targets Database DAP000177 Link_out
PharmGKB PA449409 Link_out
Drug Product Database 1913425 Link_out
RxList http://www.rxlist.com/cgi/generic/doxepin.htm Link_out
Drugs.com http://www.drugs.com/cdi/doxepin-capsules.html Link_out
Wikipedia http://en.wikipedia.org/wiki/Doxepin Link_out
ATC Codes
  • N06AA12
AHFS Codes
  • 84:08.00
  • 28:16.04.28
PDB Entries Not Available
FDA label show (588.3 KB)
MSDS show (73.4 KB)
Interactions
Drug Interactions Not Available
Food Interactions
  • Avoid alcohol.
  • Avoid excessive quantities of coffee or tea (caffeine).
  • Avoid St.John's Wort.
  • Take with food to reduce irritation.
Targets

1. Histamine H1 receptor

Pharmacological action: yes
Actions: antagonist

In peripheral tissues, the H1 subclass of histamine receptors mediates the contraction of smooth muscles, increase in capillary permeability due to contraction of terminal venules, and catecholamine release from adrenal medulla, as well as mediating neurotransmission in the central nervous system

Organism class: human
UniProt ID: P35367 Link_out
Gene: HRH1 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Tashiro M, Sakurada Y, Iwabuchi K, Mochizuki H, Kato M, Aoki M, Funaki Y, Itoh M, Iwata R, Wong DF, Yanai K: Central effects of fexofenadine and cetirizine: measurement of psychomotor performance, subjective sleepiness, and brain histamine H1-receptor occupancy using 11C-doxepin positron emission tomography. J Clin Pharmacol. 2004 Aug;44(8):890-900. Pubmed
  2. Tran VT, Lebovitz R, Toll L, Snyder SH: [3H]doxepin interactions with histamine H1-receptors and other sites in guinea pig and rat brain homogenates. Eur J Pharmacol. 1981 Apr 9;70(4):501-9. Pubmed
  3. Kano M, Fukudo S, Tashiro A, Utsumi A, Tamura D, Itoh M, Iwata R, Tashiro M, Mochizuki H, Funaki Y, Kato M, Hongo M, Yanai K: Decreased histamine H1 receptor binding in the brain of depressed patients. Eur J Neurosci. 2004 Aug;20(3):803-10. Pubmed
  4. Claro E, Arbones L, Garcia A, Picatoste F: Phosphoinositide hydrolysis mediated by histamine H1-receptors in rat brain cortex. Eur J Pharmacol. 1986 Apr 16;123(2):187-96. Pubmed
  5. Richelson E, Nelson A: Antagonism by antidepressants of neurotransmitter receptors of normal human brain in vitro. J Pharmacol Exp Ther. 1984 Jul;230(1):94-102. Pubmed
  6. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed
  7. Stahl SM: Selective histamine H1 antagonism: novel hypnotic and pharmacologic actions challenge classical notions of antihistamines. CNS Spectr. 2008 Dec;13(12):1027-38. Pubmed
  8. Singh H, Becker PM: Novel therapeutic usage of low-dose doxepin hydrochloride. Expert Opin Investig Drugs. 2007 Aug;16(8):1295-305. Pubmed
  9. Figueiredo A, Ribeiro CA, Goncalo M, Almeida L, Poiares-Baptista A, Teixeira F: Mechanism of action of doxepin in the treatment of chronic urticaria. Fundam Clin Pharmacol. 1990;4(2):147-58. Pubmed
  10. Chen X, Ji ZL, Chen YZ: TTD: Therapeutic Target Database. Nucleic Acids Res. 2002 Jan 1;30(1):412-5. Pubmed

2. Histamine H2 receptor

Pharmacological action: yes
Actions: antagonist

The H2 subclass of histamine receptors mediates gastric acid secretion. Also appears to regulate gastrointestinal motility and intestinal secretion. Possible role in regulating cell growth and differentiation. The activity of this receptor is mediated by G proteins which activate adenylyl cyclase and, through a separate G protein-dependent mechanism, the phosphoinositide/protein kinase (PKC) signaling pathway

Organism class: human
UniProt ID: P25021 Link_out
Gene: HRH2 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Beil W, Hannemann H, Sewing KF: Interaction of antidepressants and neuroleptics with histamine stimulated parietal cell adenylate cyclase and H+ secretion. Pharmacology. 1988;36(3):198-203. Pubmed
  2. Figueiredo A, Ribeiro CA, Goncalo M, Almeida L, Poiares-Baptista A, Teixeira F: Mechanism of action of doxepin in the treatment of chronic urticaria. Fundam Clin Pharmacol. 1990;4(2):147-58. Pubmed

3. Sodium-dependent noradrenaline transporter

Pharmacological action: yes
Actions: inhibitor

Amine transporter. Terminates the action of noradrenaline by its high affinity sodium-dependent reuptake into presynaptic terminals

Organism class: human
UniProt ID: P23975 Link_out
Gene: SLC6A2 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Tatsumi M, Groshan K, Blakely RD, Richelson E: Pharmacological profile of antidepressants and related compounds at human monoamine transporters. Eur J Pharmacol. 1997 Dec 11;340(2-3):249-58. Pubmed
  2. Stahl SM: Selective histamine H1 antagonism: novel hypnotic and pharmacologic actions challenge classical notions of antihistamines. CNS Spectr. 2008 Dec;13(12):1027-38. Pubmed

4. Sodium-dependent serotonin transporter

Pharmacological action: yes
Actions: inhibitor

Terminates the action of serotonine by its high affinity sodium-dependent reuptake into presynaptic terminals

Organism class: human
UniProt ID: P31645 Link_out
Gene: SLC6A4 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Tatsumi M, Groshan K, Blakely RD, Richelson E: Pharmacological profile of antidepressants and related compounds at human monoamine transporters. Eur J Pharmacol. 1997 Dec 11;340(2-3):249-58. Pubmed
  2. Stahl SM: Selective histamine H1 antagonism: novel hypnotic and pharmacologic actions challenge classical notions of antihistamines. CNS Spectr. 2008 Dec;13(12):1027-38. Pubmed

5. 5-hydroxytryptamine 2A receptor

Pharmacological action: yes
Actions: antagonist

This is one of the several different receptors for 5- hydroxytryptamine (serotonin), a biogenic hormone that functions as a neurotransmitter, a hormone, and a mitogen. This receptor mediates its action by association with G proteins that activate a phosphatidylinositol-calcium second messenger system. This receptor is involved in tracheal smooth muscle contraction, bronchoconstriction, and control of aldosterone production

Organism class: human
UniProt ID: P28223 Link_out
Gene: HTR2A Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed
  2. Maj J, Gancarczyk L, Gorszczyk L, Rawlow A: Doxepin as a blocker of central serotonin receptors. Pharmakopsychiatr Neuropsychopharmakol. 1977 Dec;10(6):318-24. Pubmed
  3. Stahl SM: Selective histamine H1 antagonism: novel hypnotic and pharmacologic actions challenge classical notions of antihistamines. CNS Spectr. 2008 Dec;13(12):1027-38. Pubmed

6. 5-hydroxytryptamine 2B receptor

Pharmacological action: yes
Actions: antagonist

This is one of the several different receptors for 5- hydroxytryptamine (serotonin), a biogenic hormone that functions as a neurotransmitter, a hormone, and a mitogen. This receptor mediates its action by association with G proteins that activate a phosphatidylinositol-calcium second messenger system

Organism class: human
UniProt ID: P41595 Link_out
Gene: HTR2B Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed
  2. Maj J, Gancarczyk L, Gorszczyk L, Rawlow A: Doxepin as a blocker of central serotonin receptors. Pharmakopsychiatr Neuropsychopharmakol. 1977 Dec;10(6):318-24. Pubmed

7. 5-hydroxytryptamine 2C receptor

Pharmacological action: yes
Actions: antagonist

This is one of the several different receptors for 5- hydroxytryptamine (serotonin), a biogenic hormone that functions as a neurotransmitter, a hormone, and a mitogen. This receptor mediates its action by association with G proteins that activate a phosphatidylinositol-calcium second messenger system

Organism class: human
UniProt ID: P28335 Link_out
Gene: HTR2C Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed
  2. Maj J, Gancarczyk L, Gorszczyk L, Rawlow A: Doxepin as a blocker of central serotonin receptors. Pharmakopsychiatr Neuropsychopharmakol. 1977 Dec;10(6):318-24. Pubmed

8. Muscarinic acetylcholine receptor M1

Pharmacological action: yes
Actions: antagonist

The muscarinic acetylcholine receptor mediates various cellular responses, including inhibition of adenylate cyclase, breakdown of phosphoinositides and modulation of potassium channels through the action of G proteins. Primary transducing effect is Pi turnover

Organism class: human
UniProt ID: P11229 Link_out
Gene: CHRM1 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed
  2. Stahl SM: Selective histamine H1 antagonism: novel hypnotic and pharmacologic actions challenge classical notions of antihistamines. CNS Spectr. 2008 Dec;13(12):1027-38. Pubmed
  3. Ehlert FJ, Delen FM, Yun SH, Liem HA: The interaction of amitriptyline, doxepin, imipramine and their N-methyl quaternary ammonium derivatives with subtypes of muscarinic receptors in brain and heart. J Pharmacol Exp Ther. 1990 Apr;253(1):13-9. Pubmed
  4. Figueiredo A, Ribeiro CA, Goncalo M, Almeida L, Poiares-Baptista A, Teixeira F: Mechanism of action of doxepin in the treatment of chronic urticaria. Fundam Clin Pharmacol. 1990;4(2):147-58. Pubmed

9. Muscarinic acetylcholine receptor M2

Pharmacological action: yes
Actions: antagonist

The muscarinic acetylcholine receptor mediates various cellular responses, including inhibition of adenylate cyclase, breakdown of phosphoinositides and modulation of potassium channels through the action of G proteins. Primary transducing effect is adenylate cyclase inhibition

Organism class: human
UniProt ID: P08172 Link_out
Gene: CHRM2 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed
  2. Ehlert FJ, Delen FM, Yun SH, Liem HA: The interaction of amitriptyline, doxepin, imipramine and their N-methyl quaternary ammonium derivatives with subtypes of muscarinic receptors in brain and heart. J Pharmacol Exp Ther. 1990 Apr;253(1):13-9. Pubmed
  3. Figueiredo A, Ribeiro CA, Goncalo M, Almeida L, Poiares-Baptista A, Teixeira F: Mechanism of action of doxepin in the treatment of chronic urticaria. Fundam Clin Pharmacol. 1990;4(2):147-58. Pubmed

10. Muscarinic acetylcholine receptor M3

Pharmacological action: yes
Actions: antagonist

The muscarinic acetylcholine receptor mediates various cellular responses, including inhibition of adenylate cyclase, breakdown of phosphoinositides and modulation of potassium channels through the action of G proteins. Primary transducing effect is Pi turnover

Organism class: human
UniProt ID: P20309 Link_out
Gene: CHRM3 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed
  2. Ehlert FJ, Delen FM, Yun SH, Liem HA: The interaction of amitriptyline, doxepin, imipramine and their N-methyl quaternary ammonium derivatives with subtypes of muscarinic receptors in brain and heart. J Pharmacol Exp Ther. 1990 Apr;253(1):13-9. Pubmed
  3. Figueiredo A, Ribeiro CA, Goncalo M, Almeida L, Poiares-Baptista A, Teixeira F: Mechanism of action of doxepin in the treatment of chronic urticaria. Fundam Clin Pharmacol. 1990;4(2):147-58. Pubmed

11. Muscarinic acetylcholine receptor M4

Pharmacological action: yes
Actions: antagonist

The muscarinic acetylcholine receptor mediates various cellular responses, including inhibition of adenylate cyclase, breakdown of phosphoinositides and modulation of potassium channels through the action of G proteins. Primary transducing effect is inhibition of adenylate cyclase

Organism class: human
UniProt ID: P08173 Link_out
Gene: CHRM4 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed
  2. Ehlert FJ, Delen FM, Yun SH, Liem HA: The interaction of amitriptyline, doxepin, imipramine and their N-methyl quaternary ammonium derivatives with subtypes of muscarinic receptors in brain and heart. J Pharmacol Exp Ther. 1990 Apr;253(1):13-9. Pubmed
  3. Figueiredo A, Ribeiro CA, Goncalo M, Almeida L, Poiares-Baptista A, Teixeira F: Mechanism of action of doxepin in the treatment of chronic urticaria. Fundam Clin Pharmacol. 1990;4(2):147-58. Pubmed

12. Muscarinic acetylcholine receptor M5

Pharmacological action: yes
Actions: antagonist

The muscarinic acetylcholine receptor mediates various cellular responses, including inhibition of adenylate cyclase, breakdown of phosphoinositides and modulation of potassium channels through the action of G proteins. Primary transducing effect is Pi turnover

Organism class: human
UniProt ID: P08912 Link_out
Gene: CHRM5 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed
  2. Ehlert FJ, Delen FM, Yun SH, Liem HA: The interaction of amitriptyline, doxepin, imipramine and their N-methyl quaternary ammonium derivatives with subtypes of muscarinic receptors in brain and heart. J Pharmacol Exp Ther. 1990 Apr;253(1):13-9. Pubmed
  3. Figueiredo A, Ribeiro CA, Goncalo M, Almeida L, Poiares-Baptista A, Teixeira F: Mechanism of action of doxepin in the treatment of chronic urticaria. Fundam Clin Pharmacol. 1990;4(2):147-58. Pubmed

13. Alpha-1A adrenergic receptor

Pharmacological action: unknown
Actions: antagonist

This alpha-adrenergic receptor mediates its action by association with G proteins that activate a phosphatidylinositol- calcium second messenger system. Its effect is mediated by G(q) and G(11) proteins

Organism class: human
UniProt ID: P35348 Link_out
Gene: ADRA1A Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed
  2. Stahl SM: Selective histamine H1 antagonism: novel hypnotic and pharmacologic actions challenge classical notions of antihistamines. CNS Spectr. 2008 Dec;13(12):1027-38. Pubmed
  3. Richelson E, Nelson A: Antagonism by antidepressants of neurotransmitter receptors of normal human brain in vitro. J Pharmacol Exp Ther. 1984 Jul;230(1):94-102. Pubmed

14. Alpha-1B adrenergic receptor

Pharmacological action: unknown
Actions: antagonist

This alpha-adrenergic receptor mediates its action by association with G proteins that activate a phosphatidylinositol- calcium second messenger system

Organism class: human
UniProt ID: P35368 Link_out
Gene: ADRA1B Link_out
Protein Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed
  2. Stahl SM: Selective histamine H1 antagonism: novel hypnotic and pharmacologic actions challenge classical notions of antihistamines. CNS Spectr. 2008 Dec;13(12):1027-38. Pubmed
  3. Richelson E, Nelson A: Antagonism by antidepressants of neurotransmitter receptors of normal human brain in vitro. J Pharmacol Exp Ther. 1984 Jul;230(1):94-102. Pubmed

15. Alpha-1D adrenergic receptor

Pharmacological action: unknown
Actions: antagonist

This alpha-adrenergic receptor mediates its effect through the influx of extracellular calcium

Organism class: human
UniProt ID: P25100 Link_out
Gene: ADRA1D Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed
  2. Stahl SM: Selective histamine H1 antagonism: novel hypnotic and pharmacologic actions challenge classical notions of antihistamines. CNS Spectr. 2008 Dec;13(12):1027-38. Pubmed
  3. Richelson E, Nelson A: Antagonism by antidepressants of neurotransmitter receptors of normal human brain in vitro. J Pharmacol Exp Ther. 1984 Jul;230(1):94-102. Pubmed

16. 5-hydroxytryptamine 1A receptor

Pharmacological action: yes
Actions: antagonist

This is one of the several different receptors for 5- hydroxytryptamine (serotonin), a biogenic hormone that functions as a neurotransmitter, a hormone, and a mitogen. The activity of this receptor is mediated by G proteins that inhibit adenylate cyclase activity

Organism class: human
UniProt ID: P08908 Link_out
Gene: HTR1A Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed
  2. Maj J, Gancarczyk L, Gorszczyk L, Rawlow A: Doxepin as a blocker of central serotonin receptors. Pharmakopsychiatr Neuropsychopharmakol. 1977 Dec;10(6):318-24. Pubmed

17. Alpha-2A adrenergic receptor

Pharmacological action: unknown
Actions: antagonist

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 oxymetazoline > clonidine > epinephrine > norepinephrine > phenylephrine > dopamine > p-synephrine > p-tyramine > serotonin = p-octopamine. For antagonists, the rank order is yohimbine > phentolamine = mianserine > chlorpromazine = spiperone = prazosin > propanolol > alprenolol = pindolol

Organism class: human
UniProt ID: P08913 Link_out
Gene: ADRA2A Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed

18. Alpha-2B adrenergic receptor

Pharmacological action: unknown
Actions: antagonist

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 > norepinephrine > epinephrine = oxymetazoline > dopamine > p-tyramine = phenylephrine > serotonin > p-synephrine / p-octopamine. For antagonists, the rank order is yohimbine > chlorpromazine > phentolamine > mianserine > spiperone > prazosin > alprenolol > propanolol > pindolol

Organism class: human
UniProt ID: P18089 Link_out
Gene: ADRA2B Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed

19. Alpha-2C adrenergic receptor

Pharmacological action: unknown
Actions: antagonist

Alpha-2 adrenergic receptors mediate the catecholamine- induced inhibition of adenylate cyclase through the action of G proteins

Organism class: human
UniProt ID: P18825 Link_out
Gene: ADRA2C Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed

20. D(2) dopamine receptor

Pharmacological action: unknown
Actions: antagonist

This is one of the five types (D1 to D5) of receptors for dopamine. The activity of this receptor is mediated by G proteins which inhibit adenylyl cyclase

Organism class: human
UniProt ID: P14416 Link_out
Gene: DRD2 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Cusack B, Nelson A, Richelson E: Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl). 1994 May;114(4):559-65. Pubmed
  2. Richelson E, Nelson A: Antagonism by antidepressants of neurotransmitter receptors of normal human brain in vitro. J Pharmacol Exp Ther. 1984 Jul;230(1):94-102. Pubmed
Enzymes

1. Cytochrome P450 2D6

Actions: substrate, inhibitor

Responsible for the metabolism of many drugs and environmental chemicals that it oxidizes. It is involved in the metabolism of drugs such as antiarrhythmics, adrenoceptor antagonists, and tricyclic antidepressants

UniProt ID: P10635 Link_out
Gene: CYP2D6 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Szewczuk-Boguslawska M, Kiejna A, Beszlej JA, Orzechowska-Juzwenko K, Milejski P: Doxepin inhibits CYP2D6 activity in vivo. Pol J Pharmacol. 2004 Jul-Aug;56(4):491-4. Pubmed
  2. Grasmader K, Verwohlt PL, Rietschel M, Dragicevic A, Muller M, Hiemke C, Freymann N, Zobel A, Maier W, Rao ML: Impact of polymorphisms of cytochrome-P450 isoenzymes 2C9, 2C19 and 2D6 on plasma concentrations and clinical effects of antidepressants in a naturalistic clinical setting. Eur J Clin Pharmacol. 2004 Jul;60(5):329-36. Epub 2004 May 28. Pubmed
  3. Kirchheiner J, Meineke I, Muller G, Roots I, Brockmoller J: Contributions of CYP2D6, CYP2C9 and CYP2C19 to the biotransformation of E- and Z-doxepin in healthy volunteers. Pharmacogenetics. 2002 Oct;12(7):571-80. Pubmed
  4. Haritos VS, Ghabrial H, Ahokas JT, Ching MS: Role of cytochrome P450 2D6 (CYP2D6) in the stereospecific metabolism of E- and Z-doxepin. Pharmacogenetics. 2000 Oct;10(7):591-603. Pubmed
  5. Flockhart DA. Drug Interactions: Cytochrome P450 Drug Interaction Table. Indiana University School of Medicine (2007). Accessed May 28, 2010.
  6. 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. Epub 2009 Nov 24. Pubmed

2. Cytochrome P450 2C19

Actions: substrate

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

UniProt ID: P33261 Link_out
Gene: CYP2C19 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Kirchheiner J, Meineke I, Muller G, Roots I, Brockmoller J: Contributions of CYP2D6, CYP2C9 and CYP2C19 to the biotransformation of E- and Z-doxepin in healthy volunteers. Pharmacogenetics. 2002 Oct;12(7):571-80. Pubmed
  2. Hartter S, Tybring G, Friedberg T, Weigmann H, Hiemke C: The N-demethylation of the doxepin isomers is mainly catalyzed by the polymorphic CYP2C19. Pharm Res. 2002 Jul;19(7):1034-7. Pubmed
  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. Epub 2009 Nov 24. Pubmed

3. Cytochrome P450 2C9

Actions: substrate

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, phenytoin, tolbutamide and losartan

UniProt ID: P11712 Link_out
Gene: CYP2C9
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Kirchheiner J, Meineke I, Muller G, Roots I, Brockmoller J: Contributions of CYP2D6, CYP2C9 and CYP2C19 to the biotransformation of E- and Z-doxepin in healthy volunteers. Pharmacogenetics. 2002 Oct;12(7):571-80. Pubmed
  2. Hartter S, Tybring G, Friedberg T, Weigmann H, Hiemke C: The N-demethylation of the doxepin isomers is mainly catalyzed by the polymorphic CYP2C19. Pharm Res. 2002 Jul;19(7):1034-7. Pubmed
  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. Epub 2009 Nov 24. Pubmed

4. Cytochrome P450 1A2

Actions: substrate

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. Most active in catalyzing 2-hydroxylation. Caffeine is metabolized primarily by cytochrome CYP1A2 in the liver through an initial N3-demethylation. Also acts in the metabolism of aflatoxin B1 and acetaminophen

UniProt ID: P05177 Link_out
Gene: CYP1A2
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Hartter S, Tybring G, Friedberg T, Weigmann H, Hiemke C: The N-demethylation of the doxepin isomers is mainly catalyzed by the polymorphic CYP2C19. Pharm Res. 2002 Jul;19(7):1034-7. Pubmed
  2. Haritos VS, Ghabrial H, Ahokas JT, Ching MS: Role of cytochrome P450 2D6 (CYP2D6) in the stereospecific metabolism of E- and Z-doxepin. Pharmacogenetics. 2000 Oct;10(7):591-603. Pubmed
  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. Epub 2009 Nov 24. Pubmed
Transporters

1. Multidrug resistance protein 1

Actions: inhibitor

Energy-dependent efflux pump responsible for decreased drug accumulation in multidrug-resistant cells

UniProt ID: P08183 Link_out
Gene: ABCB1 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Mahar Doan KM, Humphreys JE, Webster LO, Wring SA, Shampine LJ, Serabjit-Singh CJ, Adkison KK, Polli JW: Passive permeability and P-glycoprotein-mediated efflux differentiate central nervous system (CNS) and non-CNS marketed drugs. J Pharmacol Exp Ther. 2002 Dec;303(3):1029-37. Pubmed
Carriers

1. Alpha-1-acid glycoprotein 1

Actions: other/unknown

Appears to function in modulating the activity of the immune system during the acute-phase reaction

UniProt ID: P02763 Link_out
Gene: ORM1 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
SNPs: SNPJam Report Link_out

References:
  1. Ferry DG, Caplan NB, Cubeddu LX: Interaction between antidepressants and alpha 1-adrenergic receptor antagonists on the binding to alpha 1-acid glycoprotein. J Pharm Sci. 1986 Feb;75(2):146-9. Pubmed
Comments
Drug created on June 13, 2005 07:24 / Updated on October 19, 2011 12:14

This project is supported by Genome Alberta & Genome Canada, a not-for-profit organization that is leading Canada's national genomics strategy with $600 million in funding from the federal government. This project is also supported in part by GenomeQuest, Inc., an enterprise genomic information company serving the life science community.