Generic Name

Citalopram Hydrobromide

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Classification

FDA Approved Indications

• Major depressive disorder

Mechanism of Action

Citalopram selectively inhibits the reuptake of serotonin in the central nervous system, increasing serotonergic activity in the synaptic cleft.

Dosage and Administration

Adult: Starting dose typically 20 mg once daily; can be increased up to 40 mg/day based on response and tolerability.

Pediatric: Not FDA-approved for pediatric use; data limited.

Geriatric: Start at a lower dose, e.g., 10 mg/day, and titrate as needed, considering increased sensitivity and risk of side effects.

Renal Impairment: Use with caution; consider dose adjustments, especially in severe impairment.

Hepatic Impairment: Use with caution; start at lower doses with careful monitoring.

Pharmacokinetics

Absorption: Well-absorbed orally, with peak plasma levels in approximately 2-4 hours.

Distribution: Widely distributed; volume of distribution approximately 12 L/kg.

Metabolism: Primarily hepatic via CYP2C19, CYP3A4, and CYP2D6 enzymes.

Excretion: Primarily excreted in urine (cholesterols and conjugates), with a smaller amount in feces.

Half Life: Approximately 35 hours, allowing once-daily dosing.

Contraindications

• Concurrent use of Monoamine Oxidase Inhibitors (MAOIs)
• History of hypersensitivity to citalopram

Precautions

• Use cautiously in patients with a history of seizure disorders
• Monitor for increased risk of suicidal thoughts in children, adolescents, and young adults
• Monitor QT interval, especially at higher doses

Adverse Reactions - Common

• Nausea (Common)
• Insomnia (Common)
• Dry mouth (Common)
• Somnolence (Common)
• Increased sweating (Common)

Adverse Reactions - Serious

• QT prolongation (Rare)
• Serotonin syndrome (Rare)
• Suicidal thoughts or behavior (Potentially increased in young populations)

Drug-Drug Interactions

• MAOIs
• Other serotonergic agents (e.g., triptans, SNRI antidepressants)
• CYP450 inhibitors and inducers

Drug-Food Interactions

• Alcohol (may increase CNS depression and interfere with medication)
• Foods affecting CYP enzymes

Drug-Herb Interactions

• St. John's Wort (risk of serotonin syndrome)

Nursing Implications

Patient/Family Teaching

• Take medication exactly as prescribed; do not double doses.
• Report any signs of unusual bleeding, agitation, or suicidal thoughts.
• Avoid alcohol and other central nervous system depressants.
• Be aware of potential side effects like nausea, sleep disturbances, or dry mouth.
• Schedule regular follow-ups for efficacy and safety monitoring.

Special Considerations

Black Box Warnings:

• Increased risk of suicidal thoughts and behaviors in children, adolescents, and young adults

Genetic Factors: Variations in CYP2C19 genotype can affect metabolism and plasma levels.

Lab Test Interference: May slightly elevate liver enzymes; routine monitoring recommended in long-term therapy.

Overdose Management

Signs/Symptoms: Nausea, vomiting, dizziness, tremor, arrhythmias, seizures.

Treatment: Supportive care, activated charcoal if within a few hours of ingestion, cardiac monitoring, and symptomatic treatment.

Storage and Handling

Storage: Store at room temperature away from light and moisture.

Stability: Stable for at least 2 years if stored properly.