Oxybutynin reduced hot flashes in prostate cancer patients on hormone therapy, improving sleep and quality of life with minimal side effects.

A Mayo Clinic-led phase 2 trial found that oxybutynin, a drug typically used for overactive bladder, significantly reduced hot flashes in men undergoing hormone therapy for prostate cancer. Among 88 participants, those on a higher dose averaged nearly seven fewer hot flashes per day compared to placebo, with over 75% reporting at least a 50% reduction in severity. Participants also experienced improved sleep, daily functioning, and quality of life, with no serious side effects; dry mouth was the most common adverse effect. The study, part of the Alliance for Clinical Trials in Oncology, supports oxybutynin as a safe and effective option for managing this common treatment side effect, though larger trials are needed to confirm results and determine optimal dosing.