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Saw Palmetto

By

Laura Shane-McWhorter

, PharmD, University of Utah College of Pharmacy

Last full review/revision Jan 2022| Content last modified Jan 2022
CLICK HERE FOR THE PROFESSIONAL VERSION

What is saw palmetto?

Saw palmetto is a type of palm tree that grows in the southeastern United States. Its berries contain the plant’s active ingredients, which are fatty acids (fats). The plant’s berries can be made into tea. Saw palmetto is also available as tablets, capsules, and a liquid extract.

What claims are made about saw palmetto?

Saw palmetto counteracts the effects of testosterone. Many men take saw palmetto to treat benign enlargement of the prostate gland (benign prostatic hyperplasia Benign Prostatic Hyperplasia (BPH) Benign prostatic hyperplasia (BPH) is a noncancerous (benign) enlargement of the prostate gland that can make urination difficult. The prostate gland enlarges as men age. Men may have difficulty... read more ). Additional claims are that saw palmetto increases sperm production, breast size, and sexual vigor, and has anti-inflammatory and anticancer effects. It has also been used to increase scalp hair growth in people who have male pattern baldness.

Does saw palmetto work?

There is no scientific evidence to suggest that saw palmetto reverses benign prostatic hyperplasia.

Although well-designed studies did not show any benefit from saw palmetto for symptoms of an enlarged prostate gland, such as frequent urination, some evidence suggests that a specific chemical extracted from saw palmetto decreases night-time urination and increases the rate at which urine flows from the bladder.

Claims that it increases sperm production, breast size, or sexual vigor are unproved, as are claims that it has anti-inflammatory and anticancer properties. There is no clear evidence that saw palmetto increases hair growth in people with male pattern baldness.

What are the possible side effects of saw palmetto?

Headache, diarrhea, and hot flashes occasionally occur, but few serious side effects have been reported. Liver damage and pancreatitis have occurred, but it is not clear whether these were caused by saw palmetto.

What drug interactions occur with saw palmetto?

Women taking hormone therapy should consult their doctor before they take saw palmetto. Saw palmetto may interact with estrogen therapy and oral contraceptives and decrease their effectiveness. Saw palmetto may also interact with warfarin, anticoagulants, and antiplatelet drugs and result in bleeding.

Recommendations

Saw palmetto is generally considered safe and may decrease night-time urination and improve urine flow in men.

Because saw palmetto may have hormonal effects, children, women who are pregnant or who may become pregnant, and women who are breastfeeding should not take it.

People taking warfarin, other anticoagulants, or antiplatelet drugs and women taking oral birth control pills should avoid saw palmetto or talk with their doctor before taking it.

Drugs Mentioned In This Article

Generic Name Select Brand Names
DELATESTRYL
COUMADIN
NOTE: This is the Consumer Version. DOCTORS: CLICK HERE FOR THE PROFESSIONAL VERSION
CLICK HERE FOR THE PROFESSIONAL VERSION
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