Description

Simple

A medication used to treat depression, anxiety, OCD, and PTSD, as well as the symptoms of menopause such as hot flashes.

Clinical

A selective serotonin reuptake inhibitor used to treat major depressive disorder, panic disorder, OCD, social phobia, generalized anxiety disorder, the vasomotor symptoms of menopause, and premenstrual dysphoric disorder.

Overview

Paroxetine is a selective serotonin reuptake inhibitor (SSRI) drug commonly known as Paxil. It has a variety of uses, including the treatment of anxiety disorders, major depression, posttraumatic stress disorder, and symptoms of menopause, among others.[26] It was approved by the FDA in the early 1990s and marketed by SmithKline Beecham.[32,33] A unique feature of this drug is that it is highly potent and selective in its inhibition of serotonin reuptake and has little effect on other neurotransmitters.[13] Because of its potent inhibition of serotonin reuptake, paroxetine is more likely to cause withdrawal effects upon cessation. Paroxetine is well tolerated in most patients with a similar adverse effect profile to other members of its drug class.[Read more

Pharmacology

Indication

Paroxetine is indicated for the management of depression, obsessive-compulsive disorder, panic disorder, social anxiety disorder, generalized anxiety disorder, posttraumatic stress disorder.[29] One form of paroxetine,... Read more

Pharmacodynamic

Paroxetine treats the symptoms of depression, various anxiety disorders, posttraumatic stress disorder, obsessive-compulsive disorder, and the vasomotor symptoms of menopause via the inhibition of serotonin reuptake.[ Read more

Mechanism of action

Paroxetine enhances serotonergic activity via the inhibition presynaptic reuptake of serotonin by the serotonin (SERT) receptor.[ Read more

Absorption

Paroxetine is readily absorbed from the gastrointestinal tract. Due to the first-pass metabolism, the bioavailability ranges from 30-60%. Cmax is attained 2 to 8 hours after an oral dose.[ Read more

Protein binding

Paroxetine is 95% bound to plasma proteins.[7, Read more

Volume of distribution

Paroxetine has a large volume of distribution and is found throughout the body, including in the central nervous system. Only 1% of the drug is found in the plasma.[29]Paroxetine is found in the breast milk at concent... Read more

Clearance

The apparent oral clearance of paroxetine is 167 L/h.[14] The clearance... Read more

Half life

The mean elimination half-life of paroxetine is about 21 hours.[29] In healthy young subjects, mean elimination half-life was found to be 17.3 hours.[ Read more

Route of elimination

About 2/3 of a single paroxetine dose is found to be excreted in the urine and the remainder is found to be excreted in feces. Almost all of the dose is eliminated as metabolites; 3% is found to be excreted as unchanged paroxetine.[ Read more

Toxicity


The acute LD50 in mice and rats is 350 mg/kg.[35]

Overdose information

The lowest dose of paroxetine reported to lead to a fatal outcome is approximately 400 mg. The largest reported paroxetine overdose fr... Read more

Adverse Effects

Contraindications

  • Dose Form:
    • Capsule
  • Regions: US
  • Patient Conditions:
      • Name: Pregnancy
      • Drugbank Id: DBCOND0018394
  • Recommended Actions:
    • Do not administer within 14 days of MAO inhibitors
    • Do not administer with MAO inhibitors
  • Regions: US
  • Patient Conditions Associated With:
      • Name: Serotonin Syndrome
      • Drugbank Id: DBCOND0005988
  • With Categories:
      • Name: Monoamine Oxidase Inhibitors
      • Drugbank Id: DBCAT001004
      • Mesh Id: D008996
  • Regions: US
  • Patient Conditions:
      • Name: Known hypersensitivity to the drug or any of the ingredients
      • Drugbank Id: DBCOND0118758
  • Regions: US
  • With Drugs:
      • Name: Thioridazine
      • Drugbank Id: DB00679
  • Regions: US
  • With Drugs:
      • Name: Pimozide
      • Drugbank Id: DB01100

Food Interactions

  • Avoid alcohol.
  • Take with or without food. Food does not significantly affect absorption.

Interactions

Type in a drug name to check for interaction with Paroxetine
Type a drug name in the box above to get started
  • Paracetamol(acetaminophen)
  • Paxil(paroxetine)
  • Pamelor(nortriptyline)
  • Panadol(acetaminophen)
  • Patanol(olopatadine ophthalmic)
  • Pataday(olopatadine ophthalmic)
  • Parnate(tranylcypromine)
  • Pazeo(olopatadine ophthalmic)
(R)-warfarin
The serum concentration of (R)-warfarin can be increased when it is combined with Paroxetine.
(S)-Warfarin
The serum concentration of (S)-Warfarin can be increased when it is combined with Paroxetine.
1-(2-Phenylethyl)-4-phenyl-4-acetoxypiperidine
The metabolism of Paroxetine can be decreased when combined with 1-(2-Phenylethyl)-4-phenyl-4-acetoxypiperidine.
1,10-Phenanthroline
The therapeutic efficacy of Paroxetine can be decreased when used in combination with 1,10-Phenanthroline.
2,4-thiazolidinedione
The risk or severity of hypoglycemia can be increased when Paroxetine is combined with 2,4-thiazolidinedione.
2,5-Dimethoxy-4-ethylamphetamine
The risk or severity of serotonin syndrome can be increased when Paroxetine is combined with 2,5-Dimethoxy-4-ethylamphetamine.
2,5-Dimethoxy-4-ethylthioamphetamine
The risk or severity of adverse effects can be increased when 2,5-Dimethoxy-4-ethylthioamphetamine is combined with Paroxetine.
3,5-diiodothyropropionic acid
The therapeutic efficacy of 3,5-diiodothyropropionic acid can be decreased when used in combination with Paroxetine.
3,5-Diiodotyrosine
The therapeutic efficacy of 3,5-Diiodotyrosine can be decreased when used in combination with Paroxetine.
4-Bromo-2,5-dimethoxyamphetamine
The risk or severity of adverse effects can be increased when Paroxetine is combined with 4-Bromo-2,5-dimethoxyamphetamine.
4-hydroxycoumarin
The risk or severity of hemorrhage can be increased when Paroxetine is combined with 4-hydroxycoumarin.
4-Methoxyamphetamine
The metabolism of 4-Methoxyamphetamine can be decreased when combined with Paroxetine.
5-methoxy-N,N-dimethyltryptamine
The metabolism of Paroxetine can be decreased when combined with 5-methoxy-N,N-dimethyltryptamine.
6-O-benzylguanine
The metabolism of 6-O-benzylguanine can be decreased when combined with Paroxetine.
7-Nitroindazole
The risk or severity of adverse effects can be increased when Paroxetine is combined with 7-Nitroindazole.
7,8-Dichloro-1,2,3,4-tetrahydroisoquinoline
7,8-Dichloro-1,2,3,4-tetrahydroisoquinoline may increase the serotonergic activities of Paroxetine.
8-azaguanine
The metabolism of 8-azaguanine can be decreased when combined with Paroxetine.
8-chlorotheophylline
The metabolism of 8-chlorotheophylline can be decreased when combined with Paroxetine.
9-aminocamptothecin
The metabolism of 9-aminocamptothecin can be decreased when combined with Paroxetine.
9-Deazaguanine
The metabolism of 9-Deazaguanine can be decreased when combined with Paroxetine.
36 References
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