CELEXA
Clinical safety rating
cautionComprehensive clinical and safety monograph for CELEXA (CELEXA).
Selective serotonin reuptake inhibitor (SSRI); potentiates serotonergic activity in the CNS by blocking reuptake of serotonin into presynaptic neurons.
| Metabolism | Hepatic via CYP2C19 (major), CYP3A4, and CYP2D6; active metabolites: S-demethylcitalopram and didemethylcitalopram. |
| Excretion | Primarily renal: 75% as metabolites (10% as parent citalopram, 65% as desmethylcitalopram, didesmethylcitalopram, and citalopram-N-oxide). Fecal excretion accounts for approximately 20% of the dose. Biliary excretion minimal. |
| Half-life | Terminal elimination half-life is approximately 35 hours (range 23–45 h) in healthy adults. This long half-life allows once-daily dosing; steady state is reached in about 1 week. In elderly patients, half-life may extend to 45–90 hours. |
| Protein binding | Approximately 80% bound to plasma proteins (primarily albumin and α1-acid glycoprotein). Binding is independent of drug concentration. |
| Volume of Distribution | Mean Vd is 12 L/kg (range 8–16 L/kg). This large Vd indicates extensive extravascular distribution, including CNS penetration. High Vd contributes to the long half-life. |
| Bioavailability | Oral bioavailability is approximately 80% (range 60–90%). No significant first-pass metabolism. Food does not affect bioavailability. |
| Onset of Action | Oral: Antidepressant effect typically begins within 1–4 weeks, with initial improvements in sleep, appetite, and anxiety often seen in the first 2 weeks. No parenteral route available. |
| Duration of Action | Due to the long half-life, therapeutic effects persist for several days after discontinuation. To avoid withdrawal, taper over 1–2 weeks. Duration of single-dose effects: minimal; clinical benefit requires chronic dosing. |
| Molecular Weight | 324.39 Da |
| Action Class | Selective Seretonin Reuptake inhibitors (SSRIs) |
| Brand Substitutes | Lopram 10mg Tablet, C-Talo 10mg Tablet, Madam 10mg Tablet, Cetadep 10mg Tablet, Citadep 10mg Tablet, Lopram 20mg Tablet, C-Talo 20mg Tablet, Celepra 20mg Tablet, Cytop 20mg Tablet, Madam 20mg Tablet |
20 mg orally once daily initially, may increase to 40 mg once daily after at least 1 week; maximum 40 mg/day.
| Dosage form | TABLET |
| Renal impairment | GFR >20 mL/min: no adjustment; GFR ≤20 mL/min: maximum 20 mg/day; not recommended for GFR <10 mL/min. |
| Liver impairment | Child-Pugh Class A: 10 mg once daily; Child-Pugh Class B or C: maximum 20 mg/day with careful titration. |
| Pediatric use | Adolescents 12-17 years: 10 mg orally once daily initially, may increase to 20 mg once daily after 3 weeks; maximum 20 mg/day. Children <12 years: not approved. |
| Geriatric use | Patients >60 years: 10 mg orally once daily initially, maximum 20 mg once daily. |
| 1st trimester | Use in first trimester has been associated with a small increased risk of congenital cardiac malformations, particularly ventricular septal defects (VSD), based on some epidemiological studies. The absolute risk is low. Consider risks and benefits. |
| 2nd trimester | No specific fetal risks identified beyond general monitoring. Associated with persistent pulmonary hypertension of the newborn (PPHN) and neurobehavioral effects when used near term. Use with caution. |
| 3rd trimester | Use in third trimester may increase risk for persistent pulmonary hypertension of the newborn (PPHN), serotonin syndrome in the neonate, and poor neonatal adaptation syndrome (including respiratory distress, feeding difficulties, jitteriness). Taper if possible near delivery. |
Clinical note
Comprehensive clinical and safety monograph for CELEXA (CELEXA).
| Placental transfer | Citalopram crosses the placenta readily; fetal plasma concentrations are approximately 50-80% of maternal concentrations. Extensive placental transfer documented. |
| Breastfeeding | Citalopram is excreted into breast milk in small amounts. Infant serum levels are generally low, but cases of drowsiness, poor feeding, and irritability have been reported. Monitor infant for adverse effects. The American Academy of Pediatrics considers citalopram compatible with breastfeeding. |
| Lactation Rating | L2 (Limited data - compatible) |
| Teratogenic Risk | First trimester: Data insufficient to definitively assess major malformation risk; some studies suggest small increased risk of cardiac defects (e.g., septal defects). Second/Third trimester: Risk of persistent pulmonary hypertension of the newborn (PPHN), preterm birth, low birth weight; late third trimester exposure may cause neonatal adaptation syndrome (irritability, respiratory distress, feeding difficulties). |
| Fetal Monitoring | Prenatal: Screening for fetal anomalies (anatomy ultrasound) if first-trimester exposure; fetal echocardiography if concerns from population studies. Late pregnancy: Monitor for signs of PPHN, preterm labor. Neonatal: Observe for adaptation syndrome (e.g., respiratory distress, feeding intolerance, jitteriness) for at least 48 hours. Maternal: Monitor for worsening depression, suicidal ideation, serotonin syndrome (especially with co-prescribed serotonergic drugs). |
| Fertility Effects | Human data limited; citalopram may cause reversible ejaculatory dysfunction and decreased libido in men; effects on spermatogenesis or oocyte quality not well characterized. No clear evidence of impaired fertility in women; but serotonin reuptake inhibition may influence hypothalamic-pituitary-gonadal axis. Discontinuation of treatment should be weighed against risk of relapse for mood disorders. |
■ FDA Black Box Warning
Increased risk of suicidal thinking and behavior in children, adolescents, and young adults with major depressive disorder and other psychiatric disorders.
| Serious Effects |
Concomitant use with monoamine oxidase inhibitors (MAOIs) or within 14 days of discontinuing MAOI therapy (risk of serotonin syndrome)Concomitant use with linezolid or intravenous methylene blue (risk of serotonin syndrome)Known hypersensitivity to citalopram or any excipientsQTc interval prolongation (congenital or acquired) or concomitant use with other QT-prolonging agents (dose-dependent risk)
| Precautions | QT prolongation, serotonin syndrome, hyponatremia, increased risk of bleeding, activation of mania/hypomania, seizures, angle-closure glaucoma, sexual dysfunction, and discontinuation syndrome. |
| Food/Dietary | No specific food interactions. Avoid grapefruit and grapefruit juice as they may increase citalopram levels via CYP3A4 inhibition. Alcohol may exacerbate CNS depression and should be avoided. |
| Clinical Pearls | Celexa (citalopram) is an SSRI antidepressant. Key pearls: (1) Max dose 40 mg/day due to QT prolongation risk at higher doses; (2) CYP2C19 and CYP3A4 metabolism; avoid with MAOIs and linezolid; (3) Onset of therapeutic effect takes 2-4 weeks; (4) More selective for serotonin reuptake than fluoxetine or paroxetine, with fewer drug interactions; (5) May cause mild SIADH in elderly; (6) Abrupt discontinuation can cause withdrawal syndrome; (7) Electrolyte monitoring recommended in patients at risk for QT prolongation. |
| Patient Advice | Take exactly as prescribed; do not increase dose without consulting your doctor. · It may take 2-4 weeks to feel the full benefit; do not stop abruptly. · Avoid alcohol while taking this medication. · Report any symptoms of serotonin syndrome (agitation, hallucinations, rapid heart rate, fever, muscle stiffness) immediately. · Notify your doctor if you experience unusual bleeding or bruising, or if you have a history of QT prolongation or electrolyte disturbances. |
Loading safety data…