MajorAnxiolytics. Benzodiazepine derivatives×SSRI
Updated · Methodology
Mechanism
Fluvoxamine blocks CYP2C19 and CYP3A4 – both diazepam metabolic routes. Diazepam plasma levels rise 2-fold, with stronger and longer effect.
Symptoms
Marked sedation, drowsiness, ataxia. In older patients: fall and fracture risk. Symptoms appear within 3–5 days.
Management
Halve the diazepam dose when combined. Alternative benzodiazepines without CYP dependence: lorazepam or oxazepam (glucuronidated). Alternative antidepressants without CYP2C19/CYP3A4 effect: sertraline or agomelatine.
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.
Summary of a multi-drug list →
Medicine list: everything you take in one place →
Sources
- FDA: Fluvoxamine maleate tablet (Apotex Corp) – Prescribing Information section 7 (2014)– ; DailyMed setid 6eeb14df-6fcf-a737-5359-5744eb4accea
- AEMPS: Ficha técnica: Fluvoxamina (nº registro 63277), sección 4.5 (2024)– AEMPS, CIMA, nº registro 63277, sección 4.5
- AEMPS: Ficha técnica: Diazepam (nº registro 80698), sección 4.5 (2022)– AEMPS, CIMA, nº registro 80698, revisión 03/2022, sección 4.5