Moderate
Suspected
Description
Fluoxetine plus sumatriptan may potentiate serotonin syndrome risk, though the clinical evidence is mixed and the absolute risk is debated.
Mechanism
Fluoxetine inhibits serotonin reuptake and is a potent CYP2D6 inhibitor which may modestly increase sumatriptan exposure; combined serotonergic activity raises theoretical serotonin syndrome risk.
Clinical Significance
Post-marketing surveillance reports exist; many clinical guidelines permit the combination with monitoring, given frequent co-prescription in migraine.
Management
Combination is commonly used; monitor for signs of serotonin syndrome especially at treatment initiation or dose escalation.