Overview
Citalopram is a selective serotonin reuptake inhibitor (SSRI) antidepressant indicated for the treatment of major depressive disorder in adults. It works by increasing serotonin levels in the brain and carries warnings about QT prolongation, serotonin syndrome, and increased bleeding risk.
Mechanism of Action
Citalopram is a selective serotonin reuptake inhibitor (SSRI) that potently inhibits serotonin reuptake with minimal effects on norepinephrine and dopamine reuptake. It has negligible affinity for various neurotransmitter receptors including 5-HT, dopamine, adrenergic, histamine, GABA, muscarinic, and benzodiazepine receptors.
Indications
- Treatment of major depressive disorder (MDD) in adults
Common Doses
- 10 mg
- 20 mg
- 40 mg
Dosage
Typical starting dose is 20 mg once daily, with maximum recommended dose of 40 mg daily. Dosage should be reduced to 20 mg daily when used concomitantly with CYP2C19 inhibitors. Requires gradual dose reduction when discontinuing to avoid discontinuation syndrome.
Contraindications
- Concomitant use with MAOIs or within 14 days of stopping MAOIs (including linezolid or intravenous methylene blue)
- Concomitant use with pimozide
- Known hypersensitivity to citalopram or any inactive ingredients in the formulation
Side Effects
- Nausea
- Dry mouth
- Somnolence
- Insomnia
- Increased sweating
- Fatigue
- Dizziness
- Gastrointestinal disturbances
- Sexual dysfunction
- QT prolongation
- Serotonin syndrome
- Bleeding abnormalities
- Discontinuation symptoms
- Seizures
- Angle-closure glaucoma
- Hyponatremia
Interactions
- MAOIs: Contraindicated due to serotonin syndrome risk
- Pimozide: Contraindicated due to QT prolongation risk
- Other QT-prolonging drugs: Avoid concomitant use
- CYP2C19 inhibitors: Reduce maximum dose to 20 mg daily
- Other serotonergic drugs: Increased serotonin syndrome risk
- Antiplatelet agents/anticoagulants: Increased bleeding risk
Counseling Points
- Take once daily, with or without food
- Do not stop abruptly - taper gradually under medical supervision
- Report any new or worsening depression, suicidal thoughts, or unusual behavior changes
- Monitor for signs of serotonin syndrome (agitation, hallucinations, fever, sweating)
- Inform healthcare providers of all medications, including over-the-counter products
- Avoid alcohol consumption
- Use caution when driving or operating machinery until effects are known
- Report any unusual bleeding or bruising