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From the National Institutes of HealthNational Institutes of Health

Saw palmetto


What is it?

Saw palmetto is a plant. Its ripe fruit is used to make medicine.

Saw palmetto is best known for its use in decreasing symptoms of an enlarged prostate (benign prostatic hypertrophy, BPH). According to many research studies, it is effective for this use.

Saw palmetto is used for treating certain types of prostate infections. It is also sometimes used, in combination with other herbs, to treat prostate cancer.

Some people use saw palmetto for colds and coughs, sore throat, asthma, chronic bronchitis, chronic pelvic pain syndrome, and migraine headache. It is also used to increase urine flow (as a diuretic), to promote relaxation (as a sedative), and to enhance sexual drive (as an aphrodisiac).

How effective is it?

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.

The effectiveness ratings for SAW PALMETTO are as follows:

Possibly ineffective for...

  • Enlarged prostate (benign prostatic hyperplasia; BPH). There is conflicting and contradictory research about the benefits of saw palmetto for prostate symptoms. Some research has shown that saw palmetto might modestly improve symptoms such as going to the bathroom at night in some men. But higher quality and more reliable research seems to indicate that saw palmetto has little or no benefit for reducing these symptoms. Any benefit is modest at best.

Insufficient evidence to rate effectiveness for...

  • Treating prostate infections and chronic pelvic pain syndrome. Saw palmetto doesn’t seem to help prostate infections or chronic pelvic pain syndrome.
  • Prostate cancer. Research studies to date have found that taking saw palmetto doesn’t seem to prevent prostate cancer.
  • Baldness. Some men report that using saw palmetto with beta-sitosterol makes them grow more and better hair.
  • Colds and coughs.
  • Sore throat.
  • Asthma.
  • Chronic bronchitis.
  • Migraine headache.
  • Increasing breast size.
  • Reducing bleeding after prostate surgery.
  • Other conditions.
More evidence is needed to rate the effectiveness of saw palmetto for these uses.

How does it work?

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Saw palmetto doesn’t shrink the overall size of the prostate, but it seems to shrink the inner lining that puts pressure on the tubes that carry urine.

Are there safety concerns?

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Saw palmetto is LIKELY SAFE for most people. Side effects are usually mild. Some people have reported dizziness, headache, nausea, vomiting, constipation, and diarrhea. Some people have reported that saw palmetto causes impotence. But these side effects do not seem to occur any more often with saw palmetto than with a sugar pill.

There is some concern that saw palmetto might cause liver or pancreas problems in some people. 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 actual cause of these side effects.

Special precautions & warnings:

Pregnancy and breast-feeding: Saw palmetto is LIKELY UNSAFE when used during pregnancy or breast-feeding. It acts like a hormone, and this could be dangerous to the pregnancy. Don’t use during pregnancy or breast-feeding.

Surgery: Saw palmetto might slow blood clotting. There is some concern that it might cause extra bleeding during and after surgery. Stop using saw palmetto at least 2 weeks before a scheduled surgery.

Are there interactions with medications?

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Moderate

Be cautious with this combination.

Birth control pills (Contraceptive drugs)
Some birth control pills contain estrogen. Saw palmetto might decrease the effects of estrogen in the body. Taking saw palmetto along with birth control pills might decrease the effectiveness of birth control pills. If you take birth control pills along with saw palmetto, use an additional form of birth control such as a condom.

Some birth control pills include ethinyl estradiol and levonorgestrel (Triphasil), ethinyl estradiol and norethindrone (Ortho-Novum 1/35, Ortho-Novum 7/7/7), and others.

Estrogens
Saw palmetto seems to decrease estrogen levels in the body. Taking saw palmetto along with estrogen pills might decrease the effectiveness of estrogen pills.

Some estrogen pills include conjugated equine estrogens (Premarin), ethinyl estradiol, estradiol, and others.

Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)
Saw palmetto might slow blood clotting. Taking saw palmetto along with medications that also slow clotting might increase the chances of bruising and bleeding.

Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others.

Are there interactions with herbs and supplements?

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There are no known interactions with herbs and supplements.

Are there interactions with foods?

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There are no known interactions with foods.

What dose is used?

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The following doses have been studied in scientific research:

BY MOUTH:
  • For benign prostatic hyperplasia (BPH): 160 mg twice daily or 320 mg once daily.

Other names

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American Dwarf Palm Tree, Baies du Chou Palmiste, Baies du Palmier Scie, Cabbage Palm, Chou Palmiste, Ju-Zhong, Palma Enana Americana, Palmier de Floride, Palmier Nain, Palmier Nain Américain, Palmier Scie, Sabal, Sabal Fructus, Sabal serrulata, Saw Palmetto Berry, Serenoa repens, Serenoa serrulata.

Methodology

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To learn more about how this article was written, please see the Natural Medicines Comprehensive Database methodology.methodology (http://www.nlm.nih.gov/medlineplus/druginfo/natural/methodology.html).

References

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To see all references for the Saw palmetto page, please go to http://www.nlm.nih.gov/medlineplus/druginfo/natural/971.html.

  1. Barry MJ, Meleth S, Lee JY, et al. Effect of increasing doses of saw palmetto on lower urinary tract symptoms: a randomized trial. JAMA 2011;306:1344-51.
  2. Habib FK, Ross M, Ho CK, et al. Serenoa repens (Permixon) inhibits the 5alpha-reductase activity of human prostate cancer cell lines without interfering with PSA expression. Int J Cancer 2005;114:190-4.
  3. Lopatkin N, Sivkov A, Walther C, et al. Long-term efficacy and safety of a combination of sabal and urtica extract for lower urinary tract symptoms--a placebo-controlled, double-blind, multicenter trial. World J Urol 2005;23:139-46.
  4. Avins AL, Bent S, Staccone S, et al. A detailed safety assessment of a saw palmetto extract. Complement Ther Med 2008;16:147-54.
  5. Habib FK, Wyllie MG. Not all brands are created equal: a comparison of selected components of different brands of Serenoa repens extract. Prostate Cancer Prostatic Dis 2004;7:195-200.
  6. Tacklind J, MacDonald R, Rutks I, Wilt TJ. Serenoa repens for benign prostatic hyperplasia. Cochrane Database Syst Rev 2009;:CD001423.
  7. Tuncel A, Ener K, Han O, et al. Effects of short-term dutasteride and Serenoa repens on perioperative bleeding and microvessel density in patients undergoing transurethral resection of the prostate. Scand J Urol Nephrol 2009;43:377-82.
  8. Prager N, Bickett K, French N, Marcovici G. A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of 5-alpha-reductase in the treatment of androgenetic alopecia. J Altern Complement Med 2002;8:143-52.
  9. Bonnar-Pizzorno RM, Littman AJ, Kestin M, White E. Saw palmetto supplement use and prostate cancer risk. Nutr Cancer 2006;55:21-7.
  10. Jibrin I, Erinle A, Saidi A, Aliyu ZY. Saw palmetto-induced pancreatitis. South Med J 2006;99:611-2.
  1. Wilt T, Ishani A, Mac Donald R. Serenoa repens for benign prostatic hyperplasia. Cochrane Database Syst Rev 2002;:CD001423.
  2. Bent S, Kane C, Shinohara K, et al. Saw palmetto for benign prostatic hyperplasia. N Engl J Med 2006;354:557-66.
  3. Gurley BJ, Gardner SF, Hubbard MA, et al. In vivo assessment of botanical supplementation on human cytochrome P450 phenotypes: Citrus aurantium, Echinacea purpurea, milk thistle, and saw palmetto. Clin Pharmacol Ther 2004;76:428-40.
  4. Kaplan SA, Volpe MA, Te AE. A prospective, 1-year trial using saw palmetto versus finasteride in the treatment of category III prostatitis/chronic pelvic pain syndrome. J Urol 2004;171:284-8.
  5. Willetts KE, Clements MS, Champion S, et al. Serenoa repens extract for benign prostate hyperplasia: a randomized controlled trial. BJU Int 2003;92:267-70.
  6. Debruyne F, Koch G, Boyle P, et al. [Comparison of a phytotherapeutic agent (Permixon) with an alpha-blocker (Tamsulosin) in the treatment of benign prostatic hyperplasia: a 1-year randomized international study]. Eur Urol 2002;41:497-506.
  7. Markowitz JS, Donovan JL, Devane CL, et al. Multiple doses of saw palmetto (Serenoa repens) did not alter cytochrome P450 2D6 and 3A4 activity in normal volunteers. Clin Pharmacol Ther 2003;74:536-42.
  8. Vela Navarrete R, Garcia Cardoso JV, Barat A, et al. BPH and Inflammation: pharmacological effects of Permixon on histological and molecular inflammatory markers. Results of a double blind pilot clinical assay. Eur Urol 2003;44:549-55.
  9. Yale SH, Glurich I. Analysis of the inhibitory potential of Ginkgo biloba, Echinacea purpurea, and Serenoa repens on the metabolic activity of cytochrome P450 3A4, 2D6, and 2C9. J Altern Complement Med 2005;11:433-9.
  10. Goldmann WH, Sharma AL, Currier SJ, et al. Saw palmetto berry extract inhibits cell growth and Cox-2 expression in prostatic cancer cells. Cell Biol Int 2001;25:1117-24.
  11. Glemain P, Coulange C, Grapin FN, Muszynski RC. No benefit in combining tamsulosin with Serenoa repens versus tamsulosin alone on storage/filling and voiding lower urinary tract symptoms. [Abstract]. J Urol 2001;167:374.
  12. Cheema P, El-Mefty O, Jazieh AR. Intraoperative haemorrhage associated with the use of extract of Saw Palmetto herb: a case report and review of literature. J Intern Med 2001;250:167-9.
  13. Romics I, Schmitz H, Frang D. Experience in treating benign prostatic hypertrophy with Sabal serrulata for one year. Int Urol Nephrol 1993;25:565-9.
  14. Gutierrez M, Garcia de Boto MJ, Cantabrana B, Hidalgo A. Mechanisms involved in the spasmolytic effect of extracts from Sabal serrulata fruit on smooth muscle. Gen Pharmacol 1996;27:171-6.
  15. Paubert-Braquet M, Mencia Huerta JM, Cousse H, Braquet P. Effect of the lipidic lipidosterolic extract of Serenoa repens (Permixon) on the ionophore A23187-stimulated production of leukotriene B4 (LTB4) from human polymorphonuclear neutrophils. Prostaglandins Leukot Essent Fatty Acids 1997;57:299-304.
  16. Descotes JL, Rambeaud JJ, Deschaseaux P, Faure G. Placebo-controlled evaluation of the efficacy and tolerability of Permixon in benign prostatic hyperplasia after exclusion of placebo responders Clin Drug Invest 1995; 9:291-7.
  17. Carbin BE, Larsson B, Lindahl O. Treatment of benign prostatic hyperplasia with phytosterols. Br J Urol 1990;66:639-41.
  18. Adriazola-Semino M, Lozano-Ortega JL, Garcia-Cobo E, et al. [Symptomatic treatment of benign hypertrophy of the prostate. Comparative study of prazosin and serenoa repens]. Arch Esp Urol 1992; 45:211-3.
  19. Grasso M, Montesano A, Buonaguidi A, et al. Comparative effects of alfuzosin versus Serenoa repens in the treatment of symptomatic benign prostatic hyperplasia. Arch Esp Urol 1995;48:97-103.
  20. Bayne CW, Donnelly F, Ross M, Habib FK. Serenoa repens (Permixon): a 5 alpha-reductase types I and II inhibitor-new evidence in a coculture model of BPH. Prostate 1999;40:232-41.
  21. Stepanov VN, Siniakova LA, Sarrazin B, Raynaud JP. Efficacy and tolerability of the lipidosterolic extract of Serenoa repens (Permixon) in benign prostatic hyperplasia: a double-blind comparison of two dosage regimens. Adv Ther 1999;16:231-41.
  22. Strauch G, Perles P, Vergult G, et al. Comparison of finasteride (Proscar) and Serenoa repens (Permixon) in the inhibition of 5-alpha reductase in healthy male volunteers. Eur Urol 1994;26:247-52.
  23. Bayne CW, Ross M, Donnelly F, Habib FK. The selectivity and specificity of the actions of the lipido-sterolic extract of serenoa repens (permixon®) on the prostate. J Urol 2000;164:876-81.
  24. Levin RM, Das AK. A scientific basis for the therapeutic effects of Pygeum africanum and Serenoa repens. Urol Res 2000;28:201-9.
  25. 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 Urol 1992;21:309-14.
  26. Di Silverio F, Monti S, Sciarra A, et al. Effects of long-term treatment with Serenoa repens (Permixon) on the concentrations and regional distribution of androgens and epidermal growth factor in benign prostatic hyperplasia. Prostate 1998;37:77-83.
  27. Boyle P, Robertson C, Lowe F, Roehrborn C. Meta-analysis of clinical trials of permixon in the treatment of symptomatic benign prostatic hyperplasia. Urology 2000;55:533-9.
  28. Sokeland J. Combined sabal and urtica extract compared with finasteride in men with benign prostatic hyperplasia: analysis of prostate volume and therapeutic outcome. BJU Int 2000;86:439-42.
  29. Wilt T, Ishani A, Stark G, et al. Serenoa repens for benign prostatic hyperplasia. Cochrane Database Syst Rev 2000;:CD001423.
  30. Reece-Smith H, Memon A, Smart CJ, Dewbury K. The value of permixon in benign prostatic hypertrophy. Br J Urol 1986;58:36-40.
  31. Braeckman J. The extract of serenoa repens in the treatment of benign prostatic hyperplasia: a multicenter open study. Curr Ther Res 1994;55:776-85.
  32. Champault G, Patel JC, Bonnard AM. A double-blind trial of an extract of the plant Serenoa repens in benign prostatic hyperplasia. Br J Clin Pharmacol 1984;18:461-2.
  33. 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;29:231-40.
  34. Goepel M, Hecker U, Krege S, et al. Saw palmetto extracts potently and noncompetitively inhibit human alpha1-adrenoceptors in vitro. Prostate 1999;38:208-15.
  35. Gerber GS. Saw palmetto for the treatment of men with lower urinary tract symptoms. J Urol 2000;163:1408-12.
  36. Marks L, Partin AW, Epstein JI, et al. Effects of a saw palmetto herbal blend in men with symptomatic benign prostatic hyperplasia. J Urol 2000;163:1451-6.
  37. Ondrizek RR, Chan PJ, Patton WC, King A. An alternative medicine study of herbal effects on the penetration of zona-free hamster oocytes and the integrity of sperm deoxyribonucleic acid. Fertil Steril 1999;71:517-22.
  38. Ondrizek RR, Chan PJ, Patton WC, King A. Inhibition of human sperm motility by specific herbs used in alternative medicine. J Assist Reprod Genet 1999;16:87-91.
  39. USRF Research. Clinical effects of saw palmetto extract in men with symptomatic BPH webpage: www.usrf.org/spepapers.html (Accessed 23 June 2004).
  40. Marks LS, Tyler VE. Saw palmetto extract: newest (and oldest) treatment alternative for men with symptomatic benign prostatic hyperplasia. Urology 1999;53:457-61.
  41. Wilt TJ, Ishani A, Stark G, et al. Saw palmetto extracts for treatment of benign prostatic hyperplasia: a systematic review. JAMA 1998;280:1604-9.
  42. Gerber GS, Zagaja GP, Bales GT, et al. Saw palmetto (Serenoa repens) in men with lower urinary tract symptoms: effects on urodynamic parameters and voiding symptoms. Urol 1998;51:1003-7.
  43. Hamid S, Rojter S, Vierling J. Protracted cholestatic hepatitis after the use of Prostata. Ann Intern Med 1997;127:169-70.
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Last reviewed - 11/01/2011

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Page last updated: 06 September 2012