Sabal serrulata; Serenoa repens
Saw palmetto (Serenoa repens/Sabal serrulata) is a palm-like plant with berries. The berries were a staple food and medicine for the Native Americans of the southeastern United States. In the early 1900s, men used the berries to treat urinary tract problems, and even to increase sperm production and 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 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 also seems to have an anti-inflammatory effect on the prostate. At least one study has shown even greater anti-inflammatory activity when saw palmetto is combined with lycopene and selenium.Benign prostatic hyperplasia (BPH)
Evidence is mixed about whether saw palmetto works to treat BPH. Several 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. Due to the short duration (usually less than 3 months) of these studies, it is not possible to say for sure whether saw palmetto is truly effective for preventing complications of BPH. Two well-conducted studies, for example, 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
Animal studies show that saw palmetto inhibits the growth of tumor cells, indicating that it may be helpful in the treatment of prostate cancer. Other studies show that saw palmetto improves urinary tract symptoms related to BPH. While these studies are promising, more research is needed to determine whether saw palmetto is effective for these conditions.
Saw palmetto is a fan palm that grows as a tree or shrub. It can reach heights of 10 feet in warm climates, with leaf clusters that can reach 2 feet or more. It has a creeping, horizontal growth pattern. In the United States, saw palmetto 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 brownish black when ripe and are dried for medicinal use.
What Is It Made Of?
Saw palmetto's active ingredients include fatty acids, plant sterols, and flavonoids. The berries also contain high molecular weight polysaccharides (sugars), which may 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% to 95% fatty acids and sterols. Read labels carefully, and buy only from reputable companies.
How to Take ItPediatric
Saw palmetto is not recommended for children.Adult
- Liposterolic extract in capsules. One studied dosage for early stages of BPH is 160 mg, twice a day. The supplement should be a fat soluble saw palmetto extract that contains 85% to 95% fatty acids and sterols.
- Liquid extract. 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.
It may take up to 8 weeks to see beneficial effects.
The use of herbs is a time-honored approach to strengthening the body and treating disease. However, herbs can trigger side effects, and interact with other herbs, supplements, or medications. For these reasons, you should take herbs with care, under the supervision of a health care provider.
Saw palmetto is generally thought to be safe when used as directed. Side effects are very rare, although headache, nausea, diarrhea, and dizziness have been reported. In at least one case, significant bleeding during surgery was attributed to saw palmetto. There have been two reports of liver damage and one report of pancreas damage in people who took saw palmetto. But there is not enough information to know if saw palmetto was the cause of these effects.
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.
Possible InteractionsFinasteride (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, unless directed to by your physician.Antiplatelet and anticoagulant drugs (blood-thinners)
Saw palmetto may affect the blood's ability to clot, and could interfere with blood-thinning drugs, including:
- Warfarin (Coumadin)
- Clopidogrel (Plavix)
Saw palmetto may reduce the number of estrogen and androgen receptors, and thus have hormone-like effects. It may make oral contraceptives less effective, raising the risk of unplanned pregnancy.
Agbabiaka TB, Pittler MH, Wider B, Ernst E. Serenoa repens (saw palmetto): a systematic review of adverse events. Drug Saf. 2009;32(8):637-647.
Andriole GL, McCullum-Hill C, Sandhu GS, Crawford ED, Barry MJ, Cantor A. The effect of increasing doses of saw palmetto fruit extract on serum prostate specific antigen: analysis of the CAMUS randomized trial. J Urol. 2013;189(2):486-492.
Avins AL, Lee JY, Meyers CM, Barry MJ. Safety and toxicity of saw palmetto in the CAMUS trial. J Urol. 2013;189(4):1415-1420.
Bent S, Kane C, Shinohara K, et. al. Saw Palmetto for Benign Prostatic Hyperplasia. NEJM. 2006;354:557-566.
Blumenthal M, Goldberg A, Brinckmann J. Herbal Medicine: Expanded Commission E Monographs. Newton, MA: Integrative Medicine Communications; 2000:335-340.
Bone K, Mill S, eds. Principles and Practices of Phytotherapy, Modern Herbal Medicine. London: Churchill Livingstone; 2000:523-532.
Boyle P, Robertson C, Lowe F, Roehrborn C. Updated meta-analysis of clinical trials of Serenoa repens extract in the treatment of symptomatic benign prostatic hyperplasia. BJU International. 2004;93(6):751-756.
Braeckman J. The extract of Serenoa repens in the treatment of benign prostatic hyperplasia: A multicenter open study. Curr Therapeut Res. 1994;55:776-785.
Carraro JC, Raynaud JP, Koch G, et al. Comparison of phytotherapy (Permixon) with finasteride in the treatment of benign prostate hyperplasia: a randomized international study of 1,098 patients. Prostate. 1996;29(4):231-242.
Dedhia RC, McVary KT. Phytotherapy for lower urinary tract symptoms secondary to benign prostatic hyperplasia. J Urol. 2008;179(6):2119-2125.
De La Taille A, Buttyan R, Hayek O, et al. Herbal therapy PC-SPES: In vitro effects and evaluation of its efficacy in 69 patients with prostate cancer. J Urol. 2000;164:1229-1234.
Di Silverio F, D'Eramo G, Lubrano C, et al. Evidence that Serenoa repens extract displays an antiestrogenic activity in prostatic tissue of benign prostatic hypertrophy patients. Eur Uro. 1992;21:309-314.
Dull P, Reagan RW Jr, Bahnson RR. Managing benign prostatic hyperplasia. American Family Physician. 2002;66(1):77-84, 87-88.
Engelmann U, Walther C, Bondarenko B, Funk P, Schläfke S. Efficacy and safety of a combination of sabal and urtica extract in lower urinary tract symptoms. A randomized, double-blind study versus tamsulosin. Arzneimittelforschung. 2006;56(3):222-229.
Ernst E. The risk-benefit profile of commonly used herbal therapies: Ginkgo, St. John's Wort, Ginseng, Echinacea, Saw Palmetto, and Kava. Ann Intern Med. 2002;136(1):42-53.
Gerber GS. Saw palmetto for the treatment of men with lower urinary tract symptoms. J Urol. 2000;163(5):1408-1412.
Gerber GS, Fitzpatrick JM. The role of a lipido-sterolic extract of Serenoa repens in the management of lower urinary tract symptoms associated with benign prostatic hyperplasia. BJU International. 2004;94(3):338-344.
Gerber GS, Kuznetsov D, Johnson BC, Burstein JD. Randomized, double-blind, placebo-controlled trial of saw palmetto in men with lower urinary tract symptoms. Urology. 2001;58(6):960-965.
Goepel M, Hecker U, Krege S. Saw palmetto extracts potently and noncompetitively inhibit human a1-adrenoceptors in vitro. Prostate. 1998;38(3):208-215.
Hong H, Kim CS, Maeng S. Effects of pumpkin seed oil and saw palmetto oil in Korean men with symptomatic benign prostatic hyperplasia. Nutr Res Pract. 2009;3(4):323-327.
Izzo AA, Ernst E. Interactions between herbal medicines and prescribed drugs: a systematic review. Drugs. 2001;61(15):2163-2175.
Ju XB, Gu XJ, Zhang ZY, et al. Efficacy and safety of Saw Palmetto Extract Capsules in the treatment of bengin prostatic hyperplasia. Zhonghua nan ke Xue. 2015;21(12):1098-1101.
Koch E. Extracts from fruits of saw palmetto (Sabal serrulata) and roots of stinging nettle (Urtica dioica): viable alternatives in the medical treatment of benign prostatic hyperplasia and associated lower urinary tracts symptoms. Planta Med. 2001;67(6):489-500.
Marks LS, Partin AW, Epstein JI, et al. Effects of saw palmetto herbal blend in men with symptomatic benign prostatic hyperplasia. J Urol. 2000;163(5):1451-1456.
Miller LG. Herbal medicinals: selected clinical considerations focusing on known or potential drug-herb interactions. Arch Intern Med. 1998;158(20):2200-2211.
Miller RD. Miller's Anesthesia. 8th ed. Philadelphia, PA: Elsevier Saunders; 2015.
Minutoli L, Bitto A, Squadrito F, et al. Serenoa Repens, lycopene and selenium: a triple therapeutic approach to manage benign prostatic hyperplasia. Curr Med Chem. 2013;20(10):1306-1312.
Pittler MH. Complementary therapies for treating benign prostatic hype.rplasia. FACT. 2000;5(4):255-257.
Pytel YA, Vinarov A, Lopatkin N, Sivkov A, Gorilovsky L, Raynaud JP. Long-term clinical and biologic effects of the lipidosterolic extract of Serenoa repens in patients with symptomatic benign prostatic hyperplasia. Advanced Therapy. 2002;19(6):297-306.
Rakel D. Integrative Medicine. 3rd ed. Philadelphia, PA: Elsevier Saunders; 2012.
Rotblatt M, Ziment I. Evidence-Based Herbal Medicine. Philadelphia, PA: Hanley & Belfus, Inc.; 2002:327-331.
Small EJ, Frohlich MW, Bok R, et al. A prospective trial of the herbal supplement PC-SPES in patients with progressive prostate cancer. J Clin Oncol. 2000;18(21):3595-3603.
Sultan C, Terraza A, Devillier C, et al. Inhibition of androgen metabolism and binding by a liposterolic extract of "Serenoa repens B" in human foreskin fibroblasts. J Steroid Biochem. 1984;20(1):515-519.
Willetts KE, Clements MS, Champion S, Ehsman S, Eden JA. Serenoa repens extract for benign prostate hyperplasia: a randomized controlled trial. BJU International. 2003;92(3):267-270.
Wilt TJ, Ishani A, Rutks I, MacDonald R. Phytotherapy for benign prostatic hyperplasia. Public Health Nutr. 2000;3(4A):459-472.
Wilt TJ, Ishani A, Stark G, MacDonald R, Lau J, Mulrow C. Saw palmetto extracts for treatment of benign prostatic hyperplasia: a systemic review. JAMA. 1998;280(18):1604-1609.
Wolverton SE. Comprehensive Dermatologic Drug Therapy. 3rd ed. Philadelphia, PA: Elsevier Saunders; 2013.
Wyatt GK, Sikorskii A, Safikhani A, McVary KT, Herman J. Saw Palmetto for Symptom Management During Radiation Therapy for Prostate Cancer. J Pain Symptom Manage. 2016; 51(6):1046-54.
Yang Y, Ikezoe T, Zheng Z, Taguchi H, Koeffler HP, Zhu WG. Saw palmetto induces growth arrest and apoptosis of androgen-dependent prostate cancer LNCaP cells via inactivation of STAT 3 and androgen receptor signaling. Int J Oncol. 2007;31(3):593-600.
Review Date: 1/1/2017
Reviewed By: Steven D. Ehrlich, NMD, Solutions Acupuncture, a private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network. Also reviewed by the A.D.A.M Editorial team.