Drug Interaction Report

Terbinafine may increase the blood levels and effects of fesoterodine. You may need a dose adjustment if you have been taking fesoterodine and are starting treatment with terbinafine. Let your doctor know if you experience excessive drowsiness, dizziness, irregular heartbeat, blurry vision, difficulty urinating, dry mouth, headache, gastrointestinal upset, or constipation while taking these medications, as they may be symptoms caused by excessive effects of fesoterodine. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Grapefruit juice may increase the levels of fesoterodine in your body. Let your doctor know if you experience excessive drowsiness, dizziness, irregular heartbeat, blurry vision, difficulty urinating, dry mouth, headache, gastrointestinal upset, or constipation while taking fesoterodine. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.