Saw palmetto (Serenoa repens/Sabal serrulata) is a palm-like plant with berries that were a staple food and medicine for the Native Americans of the southeastern United States. In the early 1900s, the berries were used to treat urinary tract problems in men, and even to 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 a number of 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 is often combined with nettle extract to treat BPH.

Benign Prostatic Hyperplasia (BPH)

Evidence is mixed about whether saw palmetto works to treat BPH. A number of 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. But some of these studies have not been well designed, so it's not possible to say for sure that saw palmetto is truly effective. And a well-conducted study published in the February 9, 2006, edition of the New England Journal of Medicine 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

Although saw palmetto has been proposed for other conditions, there is no scientific evidence that it might be effective.

Saw palmetto is a fan palm that grows as a tree or shrub. It can reach heights of 10 feet in warm climates but has a creeping, horizontal growth pattern. In the United States, it 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 bluish-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 act to 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 - 95% fatty acids and sterols. Read labels carefully and buy only from reputable companies.

Children

Saw palmetto is not recommended for children.

Adult

• Liposterolic extract in capsules: The recommended dosages for early stages of BPH is 160 mg, twice a day. The supplement should be a fat-soluble saw palmetto extract that contains 85 - 95% fatty acids and sterols.
• Liquid extract: 5 - 6 mL per day. Note 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.

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

Saw palmetto is generally thought to be safe a when used as directed. Side effects are very rare, although mild stomach complaints and minor headaches may occur. One case of significant bleeding during surgery has been attributed to saw palmetto.

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.

Antiplatelet and anticoagulant drugs (blood-thinners) -- Saw palmetto may affect the blood's ability to clot, and could interfere with any blood-thinning drugs you are taking, including:

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

Oral contraceptives -- Because saw palmetto may have hormone-like effects, it may make oral contraceptives less effective, raising the risk of unplanned pregnancy.

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