Saw palmetto is a small tree that grows in North and Central America. The fruit from the tree has been used to ease urinary symptoms. Saw palmetto fruit can be eaten plain, dried then eaten, or made into tea or juice. It can also be taken as a pill, powder, or extract.


320 milligrams 1 to 2 times daily

What Research Shows

May Be Effective

  • Male androgenic alopecia—may increase hair growth B1

May Not Be Effective

Editorial process and description of evidence categories can be found at EBSCO NAT Editorial Process.

Editorial process and description of evidence categories can be found at EBSCO NAT Editorial Process.

Safety Notes

It is likely safe for most adults to take saw palmetto in small doses for a short time. Not enough studies have been done to say whether it is safe to use for a long period. Saw palmetto may not be safe for women who are pregnant or breastfeeding.


Talk to your doctor about any supplements or therapy you would like to use. Some can interfere with treatment or make conditions worse such as:

  • People taking blood thinners should talk to their doctor before taking saw palmetto. It may increase the risk of bleeding. C1, C2


REFA Benign Prostatic Hyperplasia

REFA1 Cai T, Mazzoli S, et al. Serenoa repens associated with Urtica dioica (ProstaMEV) and curcumin and quercitin (FlogMEV) extracts can improve the efficacy of prulifloxacin in bacterial prostatitis patients: results from a prospective randomised study. Int J Antimicrob Agents. 2009 Jun;33(6):549-553.

REFA2 Morgia G, Mucciardi G, et al. Treatment of chronic prostatitis/chronic pelvic pain syndrome category IIIA with Serenoa repens plus selenium and lycopene (Profluss) versus S. repens alone: an Italian randomized multicenter-controlled study. Urol Int. 2010;84(4):400-406.

REFA3 Barry MJ, Meleth S, et al. Effect of increasing doses of saw palmetto extract on lower urinary tract symptoms: a randomized trial. JAMA. 2011 Sep 28;306(12):1344-1351.

REFA4 Tacklind J, Macdonald R, et al. Serenoa repens for benign prostatic hyperplasia. Cochrane Database Syst Rev. 2012 Dec 12;12:CD001423.

REFA5 MacDonald R, Tacklind JW, et al. Serenoa repens monotherapy for benign prostatic hyperplasia (BPH): an updated Cochrane systematic review. BJU Int. 2012 Jun;109(12):1756-1761.

REFA6 Argirovíc A, Argirovíc D, et al. Does the addition of Serenoa repens to tamsulosin improve its therapeutic efficacy in benign prostatic hyperplasia? Vojnosanit Pregl. 2013;70(12):1091-1096.

REFA7 Coulson S, Rao A, et al. A phase II randomised double-blind placebo-controlled clinical trial investigating the efficacy and safety of ProstateEZE Max: a herbal medicine preparation for the management of symptoms of benign prostatic hypertrophy. Complement Ther Med. 2013 Jun;21(3):172-179.

REFB Male Androgenic Alopecia

REFB1 Rossi A, Mari E, et al. Comparitive effectiveness of finasteride vs Serenoa repens in male androgenetic alopecia: a two-year study. Int J Immunopathol Pharmacol. 2012 Oct-Dec;25(4):1167-1173.

REFC Safety

REFC1 Cheema P, El-Mefty O, et al. Intraoperative haemorrhage associated with the use of extract of Saw Palmetto herb: a case report and review of literature. J Intern Med. 2001 Aug;250(2):167-169.

REFC2 Milić N, Milosević N, et al. Warfarin interactions with medicinal herbs. Nat Prod Commun. 2014 Aug;9(8):1211-1216.

Revision Information

  • Reviewer: EBSCO NAT Review Board Eric Hurwitz, DC
  • Review Date: 07/2019
  • Update Date: 03/30/2020