A daily supplement of saw palmetto extract (Serenoa repens) may improve symptoms of benign prostatic hyperplasia (BPH), according to a new study in the journal, Urology (2001;58:960-5).
Symptoms associated with BPH include increased urinary urgency and frequency, straining while urinating, and a sensation of incomplete voiding after urination.
The study included 85 men over the age of 45, who scored greater than eight on the International Prostate Symptom Score (IPSS) and had no evidence of prostate cancer. The IPSS is a questionnaire used to determine the severity of urinary blockage and symptoms in men with BPH, with scores of zero to seven indicating minimal to no obstruction, eight to19 signifying mild to moderate obstruction, and 20 to 35 denoting severe obstruction.
All participants received a placebo for one month. Then, for the next six months, 41 men received 320 mg per day of a standardized extract of saw palmetto (containing 85% to 95% fatty acids and sterols) and 44 men received a placebo. In addition to the IPSS, measurements of sexual function, urinary flow rate, and side effects of treatment were assessed.
In those taking saw palmetto the IPSS decreased 2.2 points more than it did in the placebo group, a statistically significant difference. However, there were no significant differences in sexual function, urinary flow rate, or side effects between the two groups.
An advantage of saw palmetto over conventional medications is that it has fewer reported side effects, which may improve quality of life.
One possible weakness of the study is that the pre-treatment IPSS was slightly higher (worse) in the saw palmetto group than in the placebo group. With a higher initial score, it is possible that some of the improvement seen in the saw palmetto group was a statistical artefact, rather than an effect of the treatment.
Nevertheless, the results of this study are consistent with those of previously published trials demonstrating that saw palmetto is an effective treatment for the symptoms of BPH,2,3,4
One study found saw palmetto to be as effective as the drug finasteride in reducing urinary symptoms in men with mild to moderate BPH. Furthermore, finasteride significantly lowered PSA, a marker for prostate cancer, whereas saw palmetto had no effect on PSA. Taking this herb would therefore be unlikely to mask the diagnosis of prostate cancer.