A.L.A.), and the Departments of Epide-

Saw palmetto is used by over 2 million men in the United States for the treatment of benign prostatic hyperplasia and is commonly recommended as an alternative to drugs approved by the Food and Drug Administration. Methods In this double-blind trial, we randomly assigned 225 men over the age of 49 years who had moderate-to-severe symptoms of benign prostatic hyperplasia to one year of treatment with saw palmetto extract (160 mg twice a day) or placebo. The pri-mary outcome measures were changes in the scores on the American Urological Association Symptom Index (AUASI) and the maximal urinary flow rate. Secondary outcome measures included changes in prostate size, residual urinary volume after voiding, quality of life, laboratory values, and the rate of reported adverse effects. Results There was no significant difference between the saw palmetto and placebo groups in the change in AUASI scores (mean difference, 0.04 point; 95 percent confidence interval, –0.93 to 1.01), maximal urinary flow rate (mean difference, 0.43 ml pe