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Saw Palmetto

Saw palmetto berries contain the plant's active ingredients. The active ingredients, thought to be fatty acids, are unidentified but seem to inhibit 5α-reductase, thus opposing the conversion of testosterone to dihydrotestosterone. The berries can be used to make a tea, or they can be extracted into tablets, capsules, or a liquid preparation. Most formulations evaluated in clinical studies are hexane extracts of saw palmetto berries, which are 80 to 90% essential fatty acids and phytosterols.

Claims: Strong scientific evidence supports use of saw palmetto to treat symptoms of benign prostatic hyperplasia (eg, frequent urination); no evidence suggests it reverses the hyperplasia. Also, one large, well-designed study did not show any benefit.

Claims that it increases sperm production, breast size, or sexual vigor are unproved. Dose is 320 mg once/day or 160 mg bid.

Adverse effects: Headache and diarrhea may occur, but no other serious adverse effects have been reported. Saw palmetto may interact with estrogensSome Trade Names
PREMARIN
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; thus, women who are pregnant or who may become pregnant should not take it.

Last full review/revision May 2009 by Ara DerMarderosian, PhD

Content last modified May 2009

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