Paroxetine is a selective serotonin reuptake inhibitor (SSRI) widely prescribed for the management of major depressive disorder, anxiety disorders, and related conditions. As a potent and well-studied antidepressant, it functions by increasing serotonin levels in the brain, which helps improve mood, reduce anxiety, and restore emotional stability. Its efficacy, tolerability profile, and versatility across multiple indications make it a foundational agent in psychopharmacology. This product card provides a comprehensive, evidence-based overview for healthcare professionals considering paroxetine therapy.

Features

• Active ingredient: Paroxetine hydrochloride
• Available formulations: Immediate-release tablets (10 mg, 20 mg, 30 mg, 40 mg), controlled-release tablets (12.5 mg, 25 mg, 37.5 mg), oral suspension (10 mg/5 mL)
• Pharmacologic class: Selective serotonin reuptake inhibitor (SSRI)
• Half-life: Approximately 21 hours (immediate-release)
• Metabolism: Hepatic, primarily via CYP2D6
• Excretion: Renal (64%) and fecal (36%)

Benefits

• Effectively alleviates symptoms of major depressive disorder by enhancing serotonergic neurotransmission.
• Provides robust anxiolytic effects in generalized anxiety disorder, social anxiety disorder, and panic disorder.
• Reduces the frequency and severity of obsessive-compulsive behaviors in OCD patients.
• Helps manage post-traumatic stress disorder (PTSD) symptoms, including hyperarousal and avoidance.
• May improve overall quality of life and functional capacity in chronic mood and anxiety conditions.
• Available in multiple formulations to support individualized dosing and adherence.

Common use

Paroxetine is indicated for the treatment of major depressive disorder (MDD), generalized anxiety disorder (GAD), social anxiety disorder (SAD), panic disorder (PD), obsessive-compulsive disorder (OCD), and post-traumatic stress disorder (PTSD). It is also used off-label for premenstrual dysphoric disorder (PMDD), vasomotor symptoms of menopause, and certain chronic pain conditions. Treatment should be initiated under the supervision of a healthcare provider following a thorough diagnostic assessment.

Dosage and direction

Adults (MDD, GAD, SAD, PD, PTSD):
Start with 20 mg once daily, preferably in the morning. May increase in 10 mg increments at weekly intervals based on response and tolerability. Maximum dose: 50 mg/day (immediate-release) or 62.5 mg/day (controlled-release).

Adults (OCD):
Start with 20 mg daily. Effective dose range: 40–60 mg/day. Dose adjustments should occur at intervals of at least one week.

Elderly or hepatically impaired patients:
Initiate at 10 mg/day. Do not exceed 40 mg/day.

Administration:
Take with or without food. Swallow tablets whole; do not crush or chew controlled-release formulations. Shake oral suspension well before use.

Precautions

• Monitor for worsening depression, suicidality, or unusual changes in behavior, especially during initiation and dose adjustments.
• Use caution in patients with a history of mania/hypomania or seizure disorders.
• May cause hyponatremia; monitor electrolytes in at-risk populations (e.g., elderly, those on diuretics).
• Discontinuation syndrome may occur; taper gradually when stopping treatment.
• Use with caution in patients with angle-closure glaucoma or those at risk of bleeding.
• Not recommended during pregnancy unless potential benefits outweigh risks.

Contraindications

• Hypersensitivity to paroxetine or any component of the formulation.
• Concurrent use with monoamine oxidase inhibitors (MAOIs) or within 14 days of discontinuing MAOI therapy.
• Use of pimozide or thioridazine.
• Uncontrolled narrow-angle glaucoma.

Possible side effect

Common (≥1/10):

• Nausea
• Somnolence
• Headache
• Dry mouth
• Sweating
• Asthenia

Uncommon (1/100 to 1/10):

• Insomnia
• Dizziness
• Constipation
• Diarrhea
• Decreased appetite
• Sexual dysfunction

Rare (<1/100):

• Serotonin syndrome
• Hyponatremia
• Bleeding abnormalities
• Extrapyramidal symptoms
• Angle-closure glaucoma

Drug interaction

• MAOIs: Risk of serotonin syndrome; contraindicated.
• Serotonergic agents (tramadol, triptans, other SSRIs/SNRIs): Increased risk of serotonin syndrome.
• CYP2D6 substrates (e.g., tricyclic antidepressants, antipsychotics): Paroxetine may increase their plasma concentrations.
• Warfarin: May increase anticoagulant effect; monitor INR.
• NSAIDs/aspirin: Increased risk of bleeding.
• Tamoxifen: Paroxetine may reduce its efficacy via CYP2D6 inhibition.

Missed dose

If a dose is missed, take it as soon as remembered unless it is close to the next scheduled dose. Do not double the dose to make up for a missed one. Resume regular dosing schedule.

Overdose

Symptoms may include nausea, vomiting, tremor, agitation, dizziness, tachycardia, and dilated pupils. Severe overdose may lead to serotonin syndrome, seizures, or coma. There is no specific antidote; provide supportive care and symptomatic treatment. Gastric lavage or activated charcoal may be considered if presented early.

Storage

Store at 20–25°C (68–77°F). Excursions permitted to 15–30°C (59–86°F). Keep in original container, tightly closed, and protect from light and moisture. Keep out of reach of children and pets.

Disclaimer

This information is intended for healthcare professionals and is not a substitute for clinical judgment. Always consider individual patient factors, contraindications, and latest clinical guidelines before prescribing. Patients should be advised to read the medication guide and report any adverse effects promptly.

Reviews

“Paroxetine has been a cornerstone in my practice for treating both depression and anxiety disorders. Its efficacy in severe GAD is particularly notable.” — Dr. Elena Rostova, Psychiatrist
“While discontinuation can be challenging with abrupt cessation, a gradual taper minimizes symptoms. Overall, a reliable SSRI with a predictable response profile.” — Dr. Michael Torres, Clinical Pharmacologist
“Effective for OCD at higher doses, though GI side effects during initiation require management.” — Dr. Sarah Jansen, Neurologist