Despite years of controversy regarding efficacy, saw palmetto remains the most common herbal treatment for men with lower urinary tract symptoms.
Extracted from the fruit of the saw palmetto dwarf tree, the extract exerts effects by diminishing 5-alpha-reductase activity and binding to androgen receptors in prostatic cells. Saw palmetto reduces prostatic dihydrotestosterone by 32%. As a result of this anti-androgen effect, concerns have been raised as to whether serum PSA values should be adjusted accordingly.
In a new study published in the Journal of Urology (2013;189:486-492), researchers evaluated serum PSA values in 369 patients randomized to receive saw palmetto or placebo.
These men were part of the CAMUS (Complementary and Alternative Medicine for Urological Symptoms) trial, a double-blinded, randomized controlled study designed to determine whether saw palmetto extract reduced the American Urological Association symptom score compared with placebo at 72 weeks.
Even with triple the recommended dose of saw palmetto, serum PSA remained unaffected compared with placebo. These data can help guide clinicians using PSA for the early detection of prostate cancer in those patients taking this common herbal remedy.