Generic Name

Celexa

Mechanism

• Selective serotonin reuptake inhibition:
• Inhibits the presynaptic serotonin transporter (SERT) with high affinity, enhancing extracellular serotonin levels primarily in the CNS.
• Improves serotonergic neurotransmission, contributing to mood elevation and anxiolysis.
• The drug is not metabolized by hepatic CYP2D6 or CYP3A4, reducing potential drug–drug interactions common with other SSRIs.

Pharmacokinetics

Indications

• Major Depressive Disorder (MDD) in adults and adolescents ≥ 12 y.
• Panic Disorder (short‑term therapy).
• Off‑label uses: generalized anxiety, obsessive‑compulsive disorder, post‑traumatic stress disorder, and chronic pain states with mood components.

Contraindications

• Absolute contraindications:
• Concomitant use of monoamine oxidase inhibitors (MAOIs) or within 14 days of stopping MAOIs.
• Relative contraindications:
• Severe hepatic dysfunction (elevated AST/ALT > 3× ULN).
• Cardiomyopathy: QT‑interval prolongation — monitor ECG in patients ≥ 60 y or with pre‑existing QT prolongation.
• Serotonin syndrome risk with concomitant serotonergic agents (e.g., tramadol, triptans, St. John’s Wort).
• Warnings:
• Suicidal ideation or behavior in pediatric, adolescent, and young adult populations; monitor closely.
• Increases risk of bleeding with anticoagulants or NSAIDs.

Dosing

• Initial dose: 10 mg orally once daily (no dose splitting).
• Titration:
• Increase by 10 mg increments weekly to a maximum of 20 mg or 40 mg in adults if response inadequate.
• In adolescents, start at 10 mg; titrate up cautiously.
• Maintenance:
• Standard doses: 20 mg–40 mg daily.
• In severe depressive episodes or treatment‑resistant cases: up to 80 mg/day (only for specialists).
• Administration:
• Take in the morning to minimize insomnia.
• Consistent daily dosing; no need for steady‑state concentration monitoring.

Adverse Effects

Common (≥ 5 %):
• Nausea, dry mouth, constipation.
• Headache, insomnia or somnolence.
• Sexual dysfunction (decreased libido, delayed orgasm).

Serious (≤ 1 %):
• QT‑interval prolongation → torsades de pointes.
• Serotonin syndrome (especially with other serotonergic drugs).
• Severe hepatic injury (rare).
• Severe anxiety or panic spikes early in therapy.

Lab‑Related:
• Hematologic: mild neutropenia or thrombocytopenia has been documented.

Monitoring

Clinical Pearls

• QTc monitoring is critical: Even though *citalopram* has a low QT risk compared to other SSRIs, doses > 40 mg in older adults markedly increase duration; baseline ECG before high‑dose titration is advised.
• Citalopram is a “cleaner” metabolite profile compared to paroxetine; thus fewer drug interactions via CYP‑450, making it a wise first‑line SSRI in polypharmacy scenarios.
• Sexual dysfunction is dose‑dependent; consider stepping down to 10 mg if this becomes a major adherence barrier.
• In adolescents, a 10 mg starting dose avoids the higher incidence of suicidal ideation seen in high‑dose groups; titrate slowly.
• Use citalopram to bridge: For acute anxiety exacerbations combined with low‑dose benzodiazepines; taper benzodiazepines after 4–6 weeks of *citalopram* monotherapy.
• Taste disturbance: Reportable as a dose‑independent adverse event; this can be a prompt for medication review if occurring early.
• Renal impairment: Even with decreased clearance, citalopram can be safely used at standard doses, but monitor trough levels if kidney function worsens.

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• *This drug card follows ACC/AHA and NCCN guidelines for SSRIs, and incorporates current FDA prescribing information up to 2025. Consult local formularies and professional journals for the latest updates.*