Answer
Combined use is not recommended because St John's wort can accelerate fesoterodine metabolism and reduce its effect.
Sources for this answer
- Fesoterodine fumarate Dr. Reddy's/TERALEVE 8 mg Prolonged-Release Tablets — Current selected SmPCemc · Summary of Product Characteristics
- Fesoterodine fumarate Aristo 4mg tablets — Current selected SmPCemc · Summary of Product Characteristics
General medicine information. Follow the instructions for your own medicine and speak to a pharmacist or clinician about your individual circumstances.