Fesoterodine and Terbinafine interaction
Fesoterodine and Terbinafine: 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
In poor metabolizers for CYP2D6, representing a maximum CYP2D6 inhibition, C max and AUC of the active metabolite are increased 1.7- and 2-fold, respectively.
No dosing adjustments are recommended in the presence of CYP2D6 inhibitors.
CYP2D6 Inhibitors The interaction with CYP2D6 inhibitors was not tested clinically.
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.