Saw Palmetto : Uses and Health Benefits

by MedlinePlus

Saw palmetto (Serenoa repens, Sabal serrulata) is used popularly in Europe for symptoms associated with benign prostatic hypertrophy (enlargement of the prostate). Although not considered standard of care in the US, it is the most popular herbal treatment for this condition.

Historical use of saw palmetto can be traced in the Americas to the Mayans who used it as a tonic, and to the Seminoles who took the berries as an expectorant and antiseptic.

Saw palmetto was listed in the United States Pharmacopeia from 1906 to 1917, and in the National Formulary from 1926 to 1950. Saw palmetto extract is a licensed product in several European countries.

Multiple mechanisms of action have been proposed, and saw palmetto appears to possess 5-α-reductase inhibitory activity (thereby preventing the conversion of testosterone to dihydrotestosterone). Hormonal/estrogenic effects have also been reported, as well as direct inhibitory effects on androgen receptors and anti-inflammatory properties.

Synonyms

American dwarf palm tree, Arecaceae (family), cabbage palm, dwarf palm, Elusan® Prostate, IDS 89, LSESR, PA 109, Palmae (family), palmetto scrub, palmier de l' amerique du nord, palmier nain, Permixon®, Prostagutt®, Prostaserine®, sabal, Sabalfruchte (German), Sabal fructus , savpalme (Danish), saw palmetto berryserenoa, Serona repens , Serenoa serrulata Hook F., SG 291, Strogen®, WS 1473, Zwegpalme.

Also see information onpygeum (Prunus africanum, Pygeum africanum).

Evidence

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. Uses based on scientific evidence

Enlarged prostate (benign prostatic hypertrophy/BPH)

Numerous human trials report that saw palmetto improves symptoms of benign prostatic hypertrophy (BPH) such as nighttime urination, urinary flow, and overall quality of life, although it may not greatly reduce the size of the prostate. The effectiveness may be similar to the medication finasteride (Proscar®) with fewer side effects. Although the quality of these studies has been variable, overall they suggest effectiveness. Saw palmetto has not been thoroughly compared to other types of drugs used for BPH, such as doxazosin (Cardura®) or terazosin (Hytrin®). Most available studies have assessed the standardized saw palmetto product Permixon®.Although a 2003 study by Willetts et al. reports no difference between the effects of saw palmetto and placebo in 100 men over a 12-week period, overall the weight of available scientific evidence favors the effectiveness of saw palmetto.

Male-pattern hair loss

It has been suggested that saw palmetto may block some effects of testosterone and therefore reduce male pattern hair loss, similar to the medication finasteride (Propecia®). More studies are necessary before saw palmetto can be recommended for this use.

Underactive bladder

There is currently little information on the effectiveness of saw palmetto for the treatment of bladder disorders.

Prostatitis/chronic pelvic pain syndrome (CP/CPPS)

A prospective, randomized, open label, 1-year study was designed to assess the safety and efficacy of saw palmetto and finasteride in the treatment of men diagnosed with category III prostatitis/chronic pelvic pain (CP/CPPS). CP/CPPS treated with saw palmetto had no appreciable long-term improvement. In contrast, patients treated with finasteride had significant and durable improvement in multiple parameters except for voiding.

Uses based on tradition or theory

The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Acne, aphrodisiac, asthma, bladder inflammation, breast feeding, breast enlargement or reduction, bronchitis, cancer, cough, cystitis, diabetes, digestive aid, diarrhea, diuretic, dysentery, enhancing physical performance, Epstein-Barr virus, excess hair growth, expectorant, high blood pressure, hormone imbalances (estrogen or testosterone), immune stimulation, impotence, indigestion, inflammation, lactation stimulation, laryngitis, libido, menstrual pain, migraine headache, muscle or intestinal spasms, ovarian cysts, polycystic ovarian syndrome, postnasal drip, prostate cancer, reproductive organ problems, sedation, sexual vigor, sore throat, sperm production, testicular atrophy, upper respiratory tract infection, urethritis, urinary antiseptic, uterine or vaginal disorders.

Dosing

The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

Standardization

Standardization involves measuring the amount of certain chemicals in products to try to make different preparations similar to each other. It is not always known if the chemicals being measured are the "active" ingredients. A standardized extract of saw palmetto containing 80% to 95% sterols and fatty acids (liposterolic content) is often recommended.

One small study examining amounts of saw palmetto contained in preparations compared to amounts stated on labels reported a -97% to +140% difference compared to label claims. Half of the samples (3 samples) contained less than 25% of the stated amounts. Although this study examined very few saw palmetto products, it is a noteworthy example of limited quality assurance.

Adults (18 years and older)

Oral (by mouth): For enlarged prostate (benign prostatic hypertrophy), a dose of 320 milligrams daily, in one dose or two divided doses (80% to 90% liposterolic content), has been used in numerous studies. Reports suggest that 160 milligrams once daily may be as effective as twice daily. Traditional or other suggested doses that are less studied include: 1 to 2 grams of ground, dried, or whole berries daily; 2 to 4 milliliters of tincture (1:4) three times daily; 1 to 2 milliliters fluid extract of berry pulp (1:1) three times daily; or tea (2 teaspoons dried berry with 24 ounces water, simmered slowly until liquid is reduced by half) taken as 4 ounces three times daily. Teas prepared from saw palmetto berries are potentially not as effective because the active ingredients may not dissolve in water. Some experts believe that a preparation called lipidosterolic extract of Serenoa repens (LSESR) may cause fewer side effects.

Rectal (suppositories): For enlarged prostate (benign prostatic hypertrophy), limited research reports that rectal saw palmetto (640 milligrams once daily) extract is as effective as 160 milligrams taken by mouth four times daily.

Children (younger than 18 years)

Not enough information is available to recommend the use of saw palmetto in children.

About the Author

medlineplus.gov
MedlinePlus will direct you to information to help answer health questions. MedlinePlus brings together authoritative information from NLM, the National Institutes of Health (NIH), and other government agencies and health-related organizations. MedlinePlus also has extensive information about drugs, an illustrated medical encyclopedia, interactive patient tutorials, and latest health news.