Fesoterodine and Rifampin interaction
Fesoterodine and Rifampin: the Fesoterodine prescribing label describes an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Fesoterodine (Toviaz) label · effective 2026-04-07
Following induction of CYP3A4 by coadministration of rifampin 600 mg once a day, C max and AUC of the active metabolite of fesoterodine decreased by approximately 70% and 75%, respectively, after oral administration of Toviaz 8 mg.
CYP3A4 Inducers No dosing adjustments are recommended in the presence of CYP3A4 inducers, such as rifampin and carbamazepine.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.