CriticalSNRI×SSRI
Updated · Methodology
Mechanism
Dual risk. Fluvoxamine is a potent CYP1A2 inhibitor, the main duloxetine metabolic route. Duloxetine plasma levels rise 6-fold. Plus additive serotonergic load.
Symptoms
Serotonin syndrome: agitation, confusion, tremor, myoclonus, hyperreflexia. Autonomic features: sweating, tachycardia, hypertension, fever. First signs appear within hours of co-administration.
Management
The AEMPS label for duloxetine lists the combination with fluvoxamine as contraindicated. The combination is not prescribed. Choose one antidepressant: duloxetine for pain syndromes, fluvoxamine for obsessive-compulsive disorder. For augmentation, add mirtazapine.
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: Cymbalta section 7 (2017)– ; DailyMed setid 2f7d4d67-10c1-4bf4-a7f2-c185fbad64ba
- AEMPS: Ficha técnica: Duloxetina (nº registro 86282), sección 4.3 (2026)– AEMPS, CIMA, nº registro 86282, sección 4.3