Saw Palmetto


Two large, high-quality studies funded by the National Institutes of Health (NIH), each using a different preparation of saw palmetto, found it was no more effective than a placebo (an inactive substance) for BPH symptoms. Saw palmetto products are made in a variety of ways and differ in composition. Some studies other than those used in the NIH-sponsored studies have suggested that they might be helpful for BPH symptoms, but many of these studies were of low quality. No product has been conclusively shown to be effective for BPH.

There isn’t enough research on saw palmetto for conditions other than BPH to allow any conclusions to be reached.

Side Effects Of Saw Palmetto

Saw palmetto is well tolerated by most users. It may cause mild side effects, including digestive symptoms or headaches.

It does not appear to affect readings of prostate-specific antigen (PSA) levels, even when taken in higher-than-usual amounts. PSA is a protein produced by the prostate gland. PSA levels have been used to screen for prostate cancer and are also used to monitor patients who have been diagnosed with prostate cancer.

Saw palmetto has not been shown to interact with medications.

Information on safety comes primarily from studies of its use for BPH in men. Little is known about the safety or side effects when used for other conditions, especially in women or children.

Saw palmetto may be unsafe for use during pregnancy or while breastfeeding. 


Urinary tract symptoms can have several causes, including conditions such as prostate cancer that need prompt treatment. If you’re having problems with urination, it’s important to tell your health care provider.

Take charge of your health—talk with your health care providers about any complementary health approaches you use. Together, you can make shared, well-informed decisions.


All information has been provided courtesy of MedLinePlus from the National Library of Medicine and from the FDA.