This fact sheet provides basic information about the herb saw palmetto--common names, uses, potential side effects, and resources for more information. Saw palmetto grows in the southern United States.

Common Names--saw palmetto, American dwarf palm tree, cabbage palm

Latin Names--Serenoa repens, Sabal serrulata

What It Is Used For

• Saw palmetto is used mainly for urinary symptoms associated with an enlarged prostate gland (also called benign prostatic hyperplasia, or BPH).
• Saw palmetto is also used for other conditions, including chronic pelvic pain, bladder disorders, decreased sex drive, hair loss, and hormone imbalances.

How It Is Used

The ripe fruit of saw palmetto is used in several forms, including ground and dried fruit or whole berries. It is available as a liquid extract, tablets, capsules, and as an infusion or a tea.

What the Science Says

• Several small studies suggest that saw palmetto may be effective for treating BPH symptoms.
• In 2006, a large study of 225 men with moderate-to-severe BPH found no improvement with 320 mg saw palmetto daily for 1 year versus placebo. NCCAM cofunded the study with the National Institute of Diabetes and Digestive and Kidney Diseases.
• There is not enough scientific evidence to support the use of saw palmetto for reducing the size of an enlarged prostate or for any other conditions.
• Saw palmetto does not appear to affect readings of prostate-specific antigen (PSA) levels. PSA is protein produced by cells in the prostate. The PSA test is used to screen for prostate cancer and to monitor patients who have had prostate cancer.

Side Effects and Cautions

• Saw palmetto may cause mild side effects, including stomach discomfort.
• Some men using saw palmetto have reported side effects such as tender breasts and a decline in sexual desire.
• Tell your health care providers about any herb or dietary supplement you are using, including saw palmetto. This helps to ensure safe and coordinated care.

Sources:

Saw palmetto. Natural Medicines Comprehensive Database Web site. Accessed March 30, 2006.

Saw palmetto (Serenoa repens [Bartran] Small). Natural Standard Database Web site. Accessed March 30, 2006.

Saw palmetto (Serenoa repens) In: Coates P, Blackman M, Cragg G, et al., eds. Encyclopedia of Dietary Supplements. New York, NY: Marcel Dekker; 2005;635-644.

De Smet PA. Herbal remedies. New England Journal of Medicine. 2002;347(25):2046-2056.

National Cancer Institute. The Prostate-Specific Antigen (PSA) Test: Questions and Answers. National Cancer Institute Web site. Accessed at http://www.cancer.gov/cancertopics/factsheet/Detection/PSA on March 30, 2006.

Saw palmetto berry. In: Blumenthal, M, Goldberg, A, Brinckman, J, eds. Herbal Medicine: Expanded Commission E Monographs. Newton, MA: Lippincott Williams & Wilkins; 2000:335-340.

Bent S, Kane C, Shinohara K, et al. Saw palmetto for benign prostatic hyperplasia. New England Journal of Medicine. 2006;354(6):557-566.

NCCAM Publication No. D275
May 2006