Bladder Drug Cuts Hot Flashes in Prostate Cancer Patients

Men fighting prostate cancer just got surprising relief from an unexpected source: a bladder medication that dramatically reduces one of their most frustrating treatment side effects.

A new study published in the Journal of Clinical Oncology shows that oxybutynin, a drug commonly prescribed for overactive bladder, cut hot flashes by an average of seven per day in men receiving hormone therapy for prostate cancer. That's more than three times better than the placebo group, who only saw a reduction of two hot flashes daily.

The breakthrough matters for thousands of men. Between 60% and 80% of men receiving androgen-deprivation therapy experience hot flashes severe enough to disrupt sleep, mood, and daily activities. For some, the symptoms become so unbearable they consider stopping their cancer treatment entirely.

Dr. Bradley Stish, a radiation oncologist at Mayo Clinic who led the study, says these symptoms have been overlooked for too long. "Hot flashes are often underestimated in men, but they can have a real and lasting impact on quality of life during prostate cancer treatment," he explains.

The research team enrolled 88 men experiencing frequent hot flashes and randomly assigned them to receive oxybutynin at different doses or a placebo for six weeks. The results exceeded expectations. More than 75% of men taking the higher dose achieved at least a 50% reduction in how severe their hot flashes felt.

Beyond just counting fewer hot flashes, men reported something equally important: their lives got better. Participants said they slept more soundly, performed better at work, enjoyed social activities again, and felt their overall quality of life improve.

The Bright Side

The medication proved remarkably safe throughout the trial. No serious adverse events occurred, and the most common side effect was dry mouth, which increased at higher doses but remained manageable for most participants.

What makes this discovery especially promising is that oxybutynin is already FDA-approved, widely available, and affordable. Doctors can prescribe it today without waiting years for new drug approvals.

While oxybutynin has helped women manage hot flashes for years, evidence supporting its use in men has been limited until now. This study stands as one of the first randomized, placebo-controlled trials proving it works for men undergoing hormone therapy.

Researchers acknowledge that larger studies will help confirm the findings and identify the optimal dose. But the evidence already supports offering oxybutynin as a treatment option for men whose hot flashes are making cancer treatment harder to bear.

The study drew participants from academic and community cancer centers across the United States through the Alliance for Clinical Trials in Oncology, ensuring the results reflect real-world cancer care settings.

For men facing prostate cancer treatment, this research delivers something invaluable: one more tool to help them endure therapy with dignity and comfort intact.