A Bladder Pill for Hot Flashes?What the Oxybutynin Trial Showed
Menopause & HormonesArticleOxybutynin, an old overactive-bladder medicine, is now on the Menopause Society's list of recommended nonhormone treatments for hot flashes. In a 6-week trial in 150 women, many after breast cancer, it cut hot flashes more than placebo. Side effects like dry mouth were common, and longer-term brain concerns with this drug class are worth discussing.
In this article
For women who can’t or don’t want to use hormones, such as after an estrogen-sensitive cancer, the Menopause1 Society lists several nonhormone options.1 Oxybutynin, long used for overactive bladder, is one of them, rated with level I to II evidence.1
What the trial found
150 women (average age 57) with at least 28 hot flashes a week who couldn’t use estrogen took oxybutynin 2.5 mg or 5 mg twice a day, or placebo, for 6 weeks. About two-thirds were taking tamoxifen or an aromatase inhibitor after breast cancer.2
| Weekly hot flashes, change from start | |
|---|---|
| Oxybutynin 5 mg twice a day | down about 7.5 |
| Oxybutynin 2.5 mg twice a day | down about 4.8 |
| Placebo | down about 2.6 |
Both doses also improved daily interference from hot flashes and overall quality of life.2
Side effects
More common than with placebo: dry mouth, trouble urinating and belly pain, mostly mild to moderate.2 Dropout due to side effects didn’t differ from placebo.2
The longer-term question
Oxybutynin belongs to a drug class (anticholinergics) that has raised concerns about memory and dementia with long-term use in older adults. Our guide to bladder pills and dementia risk explains what studies show. The hot flash trial lasted only 6 weeks.2 Ask how long you’d take it and how you’d be monitored.
How it compares
Other nonhormone options with strong evidence include CBT, clinical hypnosis, certain antidepressants, gabapentin and fezolinetant.1 See our guides to fezolinetant, gabapentin, low-dose paroxetine and stellate ganglion block.
Questions to ask
- Is oxybutynin a fit for me, given my memory, eyes, bladder emptying and other medicines?
- Could it help both hot flashes and an overactive bladder?
- How long should I take it, and when will we reassess?
Try: “I’m on an aromatase inhibitor and my hot flashes are constant. Would oxybutynin be safe for me, and how does it compare with gabapentin or fezolinetant?”
My Body Changed. Now What? includes a Visit Brief. Use it to log how many hot flashes you have each day before and after starting any treatment. See the book.
This article is for general educational purposes only and is not medical advice. It isn't a substitute for diagnosis or treatment from a qualified healthcare professional who knows your health history. Oxybutynin can cause confusion, constipation and urinary retention, and may not be appropriate if you have glaucoma, memory problems or trouble emptying your bladder. Don't start it without a prescriber's guidance. Inability to pee, severe constipation, new confusion or eye pain needs prompt care. If you think you may be having a medical emergency, call 911 or your local emergency number right away. This article discusses published research. Girl Playbook does not endorse any specific product, test, or provider.
Girl Playbook sells this book. It provides education and worksheets, not individualized medical care.
Sources
The research behind this article, in the order it’s cited. How we source our articles.
- Menopause (abstract via PubMed), 2023The 2023 nonhormone therapy position statement of The North American Menopause Society (opens in a new tab)abcd
- JNCI Cancer Spectrum (full text via PubMed Central), 2020Oxybutynin vs Placebo for Hot Flashes in Women With or Without Breast Cancer: A Randomized, Double-Blind Clinical Trial (ACCRU SC-1603) (opens in a new tab)abcdef
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