Drug interactions
Citalopram + Fluconazole
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Overview
Fluconazole inhibits CYP2C19 (and CYP3A4), increasing citalopram exposure; both can prolong QTc, heightening risk of torsades de pointes and serious ventricular arrhythmias.
Mechanism of action
Pharmacokinetic: Fluconazole is a strong CYP2C19 and moderate CYP3A4 inhibitor, reducing citalopram metabolism and raising serum levels. Pharmacodynamic: Additive QT interval prolongation.
Clinical management
Avoid combination if possible. If necessary, limit citalopram to ≤20 mg/day when used with strong CYP2C19 inhibitors, obtain baseline and follow-up ECGs, correct K/Mg, monitor for palpitations/syncope, and consider an alternative antifungal that does not prolong QT. Discontinue or modify therapy if QTc ≥500 ms or markedly increases.
Drug reference
References
- Celexa (citalopram hydrobromide) Prescribing Information — FDA Label
- Diflucan (fluconazole) Prescribing Information — FDA Label
- Citalopram + Fluconazole: Drug Interactions — Lexicomp
Frequently asked questions
Can I take Citalopram with Fluconazole?
The interaction is rated: Major. Fluconazole inhibits CYP2C19 (and CYP3A4), increasing citalopram exposure; both can prolong QTc, heightening risk of torsades de pointes and serious ventricular arrhythmias.
How serious is the interaction between Citalopram and Fluconazole?
The interaction is rated: Major. Evidence level: High.
How is the interaction between Citalopram and Fluconazole managed?
Avoid combination if possible. If necessary, limit citalopram to ≤20 mg/day when used with strong CYP2C19 inhibitors, obtain baseline and follow-up ECGs, correct K/Mg, monitor for palpitations/syncope, and consider an alternative antifungal that does not prolong QT. Discontinue or modify therapy if QTc ≥500 ms or markedly increases.
Why do Citalopram and Fluconazole interact?
Pharmacokinetic: Fluconazole is a strong CYP2C19 and moderate CYP3A4 inhibitor, reducing citalopram metabolism and raising serum levels. Pharmacodynamic: Additive QT interval prolongation.
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