Saw palmetto (Serenoa repens/Sabal serrulata) is a palm-like plant with berries. The berries were a staple food and medicine for the Native Americans of the southeastern United States. In the early 1900s, men used the berries to treat urinary tract problems, and even to increase sperm production and boost libido. Today, the primary use of saw palmetto is to treat benign prostatic hyperplasia (BPH), a non-cancerous enlargement of the prostate gland. Researchers aren't sure exactly how saw palmetto works. But it contains plant-based chemicals that may be effective for BPH. Researchers think that saw palmetto may affect the level of testosterone in the body, and perhaps reduce the amount of an enzyme that promotes the growth of prostate cells. Saw palmetto also seems to have an anti-inflammatory effect on the prostate. At least one study has shown even greater anti-inflammatory activity when saw palmetto is combined with lycopene and selenium.

Benign prostatic hyperplasia (BPH)

Evidence is mixed about whether saw palmetto works to treat BPH. Several studies suggest that the herb is effective for treating symptoms, including too frequent urination, having trouble starting or maintaining urination, and needing to urinate during the night. The urethra, the tube that empties urine from the body, runs through the prostate gland in men. When the prostate gland is enlarged, men may have trouble urinating.

Some studies show that saw palmetto is as effective in treating symptoms as finasteride (Proscar) without side effects, such as loss of libido. Other studies suggest that saw palmetto may actually shrink the size of the prostate gland. Due to the short duration (usually less than 3 months) of these studies, it is not possible to say for sure whether saw palmetto is truly effective for preventing complications of BPH. Two well-conducted studies, for example, found that saw palmetto was no better than placebo in relieving the signs and symptoms of BPH.

It is important to receive a proper diagnosis of BPH from your doctor to rule out prostate cancer.

Other uses

Animal studies show that saw palmetto inhibits the growth of tumor cells, indicating that it may be helpful in the treatment of prostate cancer. Other studies show that saw palmetto improves urinary tract symptoms related to BPH. While these studies are promising, more research is needed to determine whether saw palmetto is effective for these conditions.

Saw palmetto is a fan palm that grows as a tree or shrub. It can reach heights of 10 feet in warm climates, with leaf clusters that can reach 2 feet or more. It has a creeping, horizontal growth pattern. In the United States, saw palmetto grows in the warm climates of the southeast coast, from South Carolina to throughout Florida. Lush, green, "saw toothed" leaves fan out from thorny stems. The plant has white flowers, which produce yellow berries. The berries turn brownish black when ripe and are dried for medicinal use.

Saw palmetto's active ingredients include fatty acids, plant sterols, and flavonoids. The berries also contain high molecular weight polysaccharides (sugars), which may reduce inflammation or strengthen the immune system.

Saw palmetto can be purchased as dried berries, powdered capsules, tablets, liquid tinctures, and liposterolic extracts. The product label should indicate that contents are standardized and contain 85% to 95% fatty acids and sterols. Read labels carefully, and buy only from reputable companies.

Pediatric

Saw palmetto is not recommended for children.

Adult

• Liposterolic extract in capsules. One studied dosage for early stages of BPH is 160 mg, twice a day. The supplement should be a fat soluble saw palmetto extract that contains 85% to 95% fatty acids and sterols.
• Liquid extract. This preparation has not been tested in any studies, so its effectiveness is not known.
• Tea. Saw palmetto can be taken as a tea. But its active ingredients (fatty acids) are not soluble in water. So tea may not be effective. It has not been tested in any studies. Capsules are recommended instead of tea.

It may take up to 8 weeks to see beneficial effects.

The use of herbs is a time-honored approach to strengthening the body and treating disease. However, herbs can trigger side effects, and interact with other herbs, supplements, or medications. For these reasons, you should take herbs with care, under the supervision of a health care provider.

Saw palmetto is generally thought to be safe when used as directed. Side effects are very rare, although headache, nausea, diarrhea, and dizziness have been reported. In at least one case, significant bleeding during surgery was attributed to saw palmetto. There have been two reports of liver damage and one report of pancreas damage in people who took saw palmetto. But there is not enough information to know if saw palmetto was the cause of these effects.

DO NOT self treat for BPH with saw palmetto. See your doctor for a proper diagnosis to rule out prostate cancer.

Saw palmetto may have effects similar to some hormones, and should not be used in pregnant or nursing women, or women who have had or are at risk for hormone-related cancers.

Saw palmetto may interfere with the absorption of iron.

Finasteride (Proscar)

Because saw palmetto may work similarly to finasteride (Proscar), you should not use this herb in combination with finasteride, or other medications used to treat BPH, unless directed to by your physician.

Antiplatelet and anticoagulant drugs (blood-thinners)

Saw palmetto may affect the blood's ability to clot, and could interfere with blood-thinning drugs, including:

• Warfarin (Coumadin)
• Clopidogrel (Plavix)
• Aspirin

Oral contraceptives and hormone replacement therapy

Saw palmetto may reduce the number of estrogen and androgen receptors, and thus have hormone-like effects. It may make oral contraceptives less effective, raising the risk of unplanned pregnancy.

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