Scientific Name: Saw Palmetto
Other Names: Cabbage Palm, Fan Palm, Sabal, Sabal serrulata, Scrub Palm, Serenoa, Serenoa repens

Who is this for?

Uses

Saw palmetto is used mainly by men to relieve the symptoms of benign prostatic hyperplasia (BPH)—a non-cancerous enlargement of the prostate gland. The prostate is part of the male reproductive system. The urethra, the tube that carries urine out of the body, passes through the prostate gland. For most men, BPH is a normal part of aging. An enlarged prostate, however, may cause men to have trouble starting or maintaining urination, urinate more often, have urine leaks, or need to urinate during the night.

Numerous laboratory, animal, and human studies have been done to test the effectiveness of saw palmetto for BPH. In general, results have been positive—possibly due to saw palmetto’s potential ability to block at least partially the effects of an enzyme that promotes and maintains prostate cell growth. However, many of the human studies were not well controlled and many of them involved only small numbers of participants. Therefore, some results may not be very reliable. In one animal study, saw palmetto appeared to cause the prostate to shrink, but while using saw palmetto seemed to help relieve the symptoms of BPH for humans, it had little or no effect on prostate size. It also showed no effects on blood levels of prostate-specific antigen (PSA), a protein that is produced by prostate cancer cells. Because PSA circulates in the blood, it can be tested easily to determine if prostate enlargement is caused by cancer.

Saw palmetto has also been reported to have mild anti-inflammatory, antiseptic, diuretic, and sedative properties. These effects are based largely on case reports with little study evidence to support them. Results from a small study of men who suffered from long-term inflammation of the prostate showed improvement in some markers of inflammation after 3 months of treatment with saw palmetto. Conversely, a separate, year-long study also involving a small group of men with chronically inflamed prostates found that taking saw palmetto had no significant effects on either the symptoms or the inflammation, itself. More studies are underway to evaluate these possible effects of saw palmetto.

Results from one small human study and several unconfirmed reports from individuals taking saw palmetto to treat BPH seem to indicate that saw palmetto may stimulate hair growth. Some women reportedly use it to increase breast size, and it has also been promoted to enhance sexual desire for both men and women. Much more scientific evidence is needed to support any of these possible uses.

Because saw palmetto contains plant sterols with hormonal effects, pregnant women and women who are breast-feeding should not use it. Women with hormone-dependent breast cancer should also avoid taking it.

Due to its potential hormonal effects, saw palmetto should not be taken by children.

Precautions

Saw palmetto has not been proven effective in treating prostate cancer and it does not have any proven effectiveness for urinary tract infections.

What side effects should I watch for?

Major Side Effects

One case of recurring pancreatitis with hepatitis is attributed to saw palmetto use by an individual who recovered after saw palmetto was stopped. Pancreatitis is painful and sometimes life-threatening inflammation of the pancreas.

Another case of non-viral hepatitis has been reported in a man using a combination product that contained saw palmetto. The exact cause of the hepatitis was not identified conclusively, however.

At least one case of impotence also seems to be associated with taking saw palmetto, but the incidence of impotence among participants in clinical studies was similar for both saw palmetto and placebo (inactive sugar pills).

Less Severe Side Effects

Individuals taking saw palmetto in clinical studies have reported only mild and temporary side effects including:

• Constipation
• Diarrhea
• Dizziness
• Headache
• Nausea
• Upset stomach

What interactions should I watch for?

Prescription Drugs

In studies and case reports, saw palmetto has been shown to increase the time blood needs to clot. When it is taken with an antiplatelet or an anticoagulant drug, the effect of the drug may be increased, resulting in uncontrolled bleeding.

• Antiplatelets include clopidogrel and Ticlid
• Anticoagulants include heparin and warfarin

Because it has hormonal activity, saw palmetto may interfere with the effectiveness of oral contraceptives and hormone replacement therapy.

Non-prescription Drugs

Saw palmetto can affect the ability of blood to clot after an injury. Aspirin can also delay clotting, so saw palmetto should not be taken at the same time aspirin is being taken.

Herbal Products

If saw palmetto is used with other herbs that affect blood clotting, bleeding may occur. Individuals who take any herbal product should check with a pharmacist to see if it affects blood clotting. Some of the most common herbal products with possible inhibiting effects on blood clotting are:

• Danshen
• Devil's Claw
• Garlic
• Ginger
• Ginkgo
• Ginseng
• Horse Chestnut
• Papain
• Red Clover

Some interactions between herbal products and medications can be more severe than others. The best way for you to avoid harmful interactions is to tell your doctor and/or pharmacist what medications you are currently taking, including any over-the-counter products, vitamins, and herbals. For specific information on how saw palmetto interacts with drugs, other herbals, and foods and the severity of those interactions, please use our Drug Interactions Checker to check for possible interactions.

Should I take it?

Saw palmetto grows extensively in warm coastal areas of southeastern North American, parts of Africa, and southern Europe. The saw palmetto is easily recognized by its long, thin "saw tooth-edged" leaves and by its characteristic bushy shape. Its trunks may reach 10 feet or more in length, but they tend to lie along the ground, making the fruits relatively easy to reach, although harvesting them is complicated by the sharp spikes that line saw palmetto leaves. It is an evergreen with silvery or bluish leaves. In the spring and summer, multiple small white flowers bloom on long stalks, which sprout from the top of the trunk. Its large clusters of olive-sized fruits turn dark blue when they are ripe in late summer and autumn. Although they are said to taste somewhat like soap, saw palmetto fruits frequently are eaten fresh or made into jam. They also provide food sources for birds and animals native to the areas where they grow. For use in medicine, ripe fruits are collected in the autumn, the seeds are removed, and the fruits are dried. Most saw palmetto fruit comes from plants that grow wild, but saw palmetto may also be cultivated on farms or in large greenhouses where cold winters prevent its growing outdoors.

Dosage and Administration

Dried saw palmetto fruits are marketed widely. Saw palmetto is also available commercially as capsules, tablets, and several liquid dosage forms. Oral saw palmetto products should be standardized to contain 80% or more of the active ingredients, which are fatty acids. Standardization by the manufacturer assures the same amount of active ingredient in every batch of the commercial preparation. Standardization of herbal products is not required by the U.S. Food and Drug Administration (FDA), so not every product will contain the same amounts of active ingredients. Recently, an analysis of 14 brands of saw palmetto revealed that many of the products did not contain the amounts of active ingredients that were indicated on the labels.

Regular dosing of saw palmetto may be needed for up to 6 weeks before symptom relief may begin and some study participants did not notice changes until saw palmetto had been used for 6 months or longer. Typical dosing ranges from 320mg to 1800mg of a standardized commercial saw palmetto product daily—in one dose, two doses, or three doses. Alternately, 1000 mg to 2000 mg (one gram to 2 grams) of the dried fruits can be eaten each day. A tea can be made by soaking 500 mg to 1000 mg (0.5 gram to one gram) of the dried fruits in about 5 ounces of boiling water for 5 minutes to 10 minutes and then straining out the fruits before drinking the tea. Some individuals consume the softened fruits after using them to make tea. Saw palmetto tea is usually taken three times a day, but since the active ingredients are not water-soluble, the effectiveness of saw palmetto tea is questionable.

Saw palmetto is often combined with other herbal or nutritional supplements, such as nettle root and Pygeum africanum, that may also have anti-BPH effects. The FDA has warned against the use of specific combination products, however, because some of them may contain an ingredient that could affect bleeding. A healthcare professional should be consulted before self-treatment with any product that contains saw palmetto is started.

Summary

The main use of saw palmetto is to treat the urinary symptoms of benign prostatic hyperplasia (BPH). Saw palmetto has not been proven effective in treating prostate cancer, however, and it does not have any effectiveness for urinary infections.

Risks

Saw palmetto contains plant sterols that have hormonal effects, so children, women who are pregnant or breast-feeding, and women who have hormone-dependent breast cancer should avoid using it.

Side Effects

Rare and unsubstantiated cases of non-viral hepatitis and impotence have been reported in men using saw palmetto, but the exact causes of the side effects are not known. In clinical studies, taking saw palmetto has caused occasional constipation, diarrhea, dizziness, headache, nausea, or upset stomach.

Interactions

If it is taken with drugs or other herbals that have antiplatelet or anticoagulant effects, saw palmetto can lengthen bleeding time. Saw palmetto's hormonal effects may interfere with the effectiveness of oral contraceptives and hormone replacement therapy.

Last Revised September 9, 2007

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Last Revised September 9, 2007

Note: The above information is not intended to replace the advice of your physician, pharmacist, or other healthcare professional. It is not meant to indicate that the use of the product is safe, appropriate, or effective for you.

In general, herbal products are not subject to review or approval by the U.S. Food and Drug Administration (FDA). They are not required to be standardized, meaning that the amounts of active ingredients or contaminants they contain may vary between brands or between different batches of the same brand. Not all of the risks, side effects, or interactions associated with the use of herbal products are known because few reliable studies of their use in humans have been done.

This information is provided for your education only. Please share this information with your healthcare provider and be sure that you talk to your doctor and pharmacist about all the prescription and non-prescription medicines you take before you begin to use any herbal product.

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