Za Pharmacy
Drugs, Supplies and Delivery
Citalopram the SSRI Antidepressant
Citalopram is a selective serotonin reuptake inhibitor (SSRI) widely prescribed for the treatment of depression and certain anxiety disorders. Known for its efficacy and tolerability, citalopram is a first-line agent in managing major depressive disorder (MDD). This article synthesizes information from the British National Formulary (BNF), Lippincott Textbook of Pharmacology, and Lange Basic & Clinical Pharmacology to provide a detailed overview of citalopram, including its mechanism of action, therapeutic uses, dosing, side effects, precautions, drug interactions, and availability.
Citalopram selectively inhibits the reuptake of serotonin (5-HT) at the presynaptic neuronal membrane, increasing serotonin availability in the synaptic cleft. This enhances serotonergic neurotransmission, which is associated with improved mood and emotional regulation (Lippincott Textbook of Pharmacology). Unlike older antidepressants, citalopram has minimal affinity for histamine, acetylcholine, or adrenergic receptors, reducing the risk of anticholinergic or sedative side effects (Lange Basic & Clinical Pharmacology).
- Major Depressive Disorder (MDD):
- First-line treatment for acute episodes and maintenance therapy to prevent relapse (BNF).
- Generalized Anxiety Disorder (GAD):
- Approved for managing chronic anxiety symptoms.
- Off-Label Uses:
- Panic disorder, social anxiety disorder, and obsessive-compulsive disorder (OCD) in some cases (Lange Basic & Clinical Pharmacology).
- Adults:
- Initial Dose: 20 mg once daily, preferably in the morning or evening.
- Maintenance Dose: 20–40 mg daily; maximum 40 mg/day due to QT prolongation risks.
- Elderly or Hepatically Impaired Patients:
- Maximum Dose: 20 mg/day (BNF).
- Titration:
- Adjust after 3–4 weeks based on response and tolerability.
Administration:
- Can be taken with or without food.
- Avoid abrupt discontinuation; taper gradually over weeks to prevent withdrawal symptoms (Lippincott).
- Common: Nausea, dry mouth, sweating, insomnia, and somnolence (BNF).
- Serious:
- QT Prolongation: Dose-dependent risk of arrhythmias (e.g., torsades de pointes).
- Serotonin Syndrome: Agitation, hyperthermia, and autonomic instability (rare but life-threatening).
- Hyponatremia: Especially in elderly patients (Lange Basic & Clinical Pharmacology).
- Contraindications:
- Concurrent use of MAO inhibitors (risk of serotonin syndrome).
- Congenital long QT syndrome or significant cardiac disease (BNF).
- Monitoring:
- ECG monitoring recommended in patients with cardiac risk factors or doses >20 mg/day.
- Serum sodium levels in elderly patients (Lippincott).
- Pregnancy/Lactation:
- Use with caution; potential neonatal withdrawal or persistent pulmonary hypertension (PPHN) (BNF).
- MAO Inhibitors: Risk of serotonin syndrome; allow a 14-day washout period.
- QT-Prolonging Drugs (e.g., amiodarone, antipsychotics): Synergistic risk of arrhythmias.
- CYP2C19 Inhibitors (e.g., omeprazole): Increase citalopram levels; consider dose reduction.
- NSAIDs/Anticoagulants: Elevated bleeding risk due to SSRI-induced platelet dysfunction (Lange Basic & Clinical Pharmacology).
Citalopram is the generic name. It is marketed under the brand name Celexa® in some regions. Generic formulations are widely available as:
- Tablets: 10 mg, 20 mg, 40 mg.
- Oral Solution: 10 mg/5 mL (BNF).
