duloxetine × fluvoxamine

Dual risk. Fluvoxamine is a potent CYP1A2 inhibitor, the main duloxetine metabolic route. Duloxetine plasma levels rise 6-fold. Plus additive serotonergic load.

Serotonin syndrome: agitation, confusion, tremor, myoclonus, hyperreflexia. Autonomic features: sweating, tachycardia, hypertension, fever. First signs appear within hours of co-administration.

The combination is not prescribed. Choose one antidepressant: duloxetine for pain syndromes, fluvoxamine for obsessive-compulsive disorder. For augmentation, add mirtazapine.