Serenoa repens (W.Bartram) Small

Last updated: 24 Aug 2016

Scientific Name

Serenoa repens (W.Bartram) Small   


Brahea serrulata (Michx.) H.Wendl., Chamaerops serrulata Michx., Corypha obliqua W.Bartram, Corypha repens W.Bartram, Diglossophyllum serrulatum (Michx.) H.Wendl. ex Salomon, Sabal serrulata (Michx.) Schult.f., Serenoa serrulata (Michx.) Hook.f. ex B.D.Jacks. [1]

Vernacular Name

English Saw palmetto [2], palmetto scrub, American dwarf, dwarf palmetto, sabal japa, cabbage palm [3]
Brazil Serenoa [2].

Geographical Distributions

Serenoa repens is indigenous to Florida, South Carolina, and West Indies. [3]

Botanical Description

S. repens is a member of the family Arecaceae [1]. It is a creeping shrub with stems usually creeping, branched, sometimes ascending, to 1-3 m. [4]

The leaves are yellow-green, green, or silvery green, and stiff. The petioles are finely to strongly serrate with hastula present on both sides of leafabaxially and adaxially. [4]

The flowers are creamy white, fragrant, and measure 4-5 mm. [4]

The fruits are ripening from green through orange to black, measure about 2 cm length with 1 m diametre. [4]


No documentation.

Chemical Constituent

Hexane and diethyl ether extract of S. repens has been reported to contain free fatty acids, esterified fatty acids, phytosterol, aliphatic alcohols, and polypyrenic compound. [5]

Plant Part Used

No documentation.

Traditional Use

No documentation.

Preclinical Data


Benign prostatic hyperplasia (BPH) treatment

S. repens showed a potential to treat BPH that caused by the stimulatation of 5 α-dihydrotestosterone (DHT) to produce prostate cells. Excessive formation of DHT leads to overproduction and enlargement of the prostate (hyperplasia). Another factor is the presence of estrogen which inhibits the elimination of DHT. There are several reported mechanisms of action of S. repens for use in treating benign prostatic hyperplasia (BPH). They include inhibition of DHT production, inhibition of the binding of DHT to its receptors and promoting its breakdown. [6][7][8]

S. repens is believed that its antiestrogenic effect may be more important than any of its other actions. S. repens inhibits 5-a reductase, an enzyme that catalyzes the conversion of testosterone into DHT, having α-1 and α-2 adrenergic blocking capabilities. [9][10]


S. repens extracts are effective against various cancer cells lines, inducing growth arrest and apoptosis [11][12][13][14]. β-sitosterol and stigmasterol are reported to have antitumor activity in laboratory studies [15].

Immunostimulating activity

In vitro study showed immune stimulating activity in a 4:1 w/v water extract of S. repens fruit which increased the phagocytic activity by 36%. The polysaccharide fraction of S. repens berry (10 mg/kg) produced a much higher carbon clearance value than echinacea (Echinacea purpurea) or Siberian ginseng (Eleutherococcus senticosus) and showed a higher value than any of nine other plant extracts in laboratory mice. However, the standardized and alcohol extracted preparations of S. repens are not extracted with water, so would not contain these immune stimulating polysaccharides – use encapsulated raw berries. [16] 


No documentation.

Clinical Data

Clinical findings

Various clinical studies have reported the positive benefits of using standardized S. repens extracts in the prevention of BPH [17]S. repens has compared favorably with drug treatments for BPH including finasteride and tamsulosin [18].

A 2009 Cochrane Database System Review looked at studies in 5222 men with BPH. The authors concluded that S. repens was not more effective than placebo for treatment of urinary symptoms consistent with BPH [19]. However, a combination of S. repens and nettle (Urtica dioica) in 219 people reported significant benefits in LUTS (International Prostate Symptom Score) [20]. Similar results using S. repens and urtica extract in combination have been reported in other human trials [21][22]. A 12 month Korean study found a combination of S. repens and pumpkin seed oil in 47 men with BPH was found to improve the quality of life in these patients [23]S. repens in combination with curcumin (Curcuma longa) and the bioflavonoid quercitin improved the efficacy of in conjunction with the antiboitic prulifloxacin in treating bacterial prostatitis [24].

S. repens is mainly used in men suffering from benign prostatic hyperplasia (BPH). There have been several studies reporting the effects of saw palmetto in BPH, some as being at least as good as the common pharmaceutical drugs used to treat BPH. [25][26][27][28]

A monocentric, randomised versus control group studyhas been carried out to 108 patients with benign prostatic hyperplasia. Pretreatment of S. repens to patients with benign prostatic hyperplasia undergoing a transurethral resection of prostate operation seemed to have improved efficacy of the procedure itself and experienced a reduced risk of complications. [29]

A therapeutic effect of oral administration of S. repens extract at 160 mg twice-daily to 505 patients with mild-to-moderate symptoms of benign prostatic hyperplasia (BPH) patients was studied during a 3-month open trial. BPH is thought to be caused by an increase in the conversion of testosterone to 5-a dihydrotestosterone (DHT) in the prostate. [30]

A randomaized, double-blind placebo-controlled study was performed in 35 benign prostatic hypertrophy (BPH) patients that never been treated before to study the effect of S. repens following 3 months administration prior to their operation of transvesical adenomectomy. S. repens is reported to exert an antiestrogenic effect, as well as an antiandrogenic effect. [25]


Concern has been raised regarding the effect that S. repens use can have on serum prostate specific antigen (PSA). Research shows that S. repens use apparently has no effect on the PSA level [31][32][33]. Proprietary herbal blends that contain saw palmetto as well as other products have been formulated to improve symptoms associated with the prostate. Studies and case reports show that these blends can alter the PSA level [34][35].

This dietary supplement is considered safe when used in accordance with proper dosing guidelines. [36][37]

Interaction & Depletion

No documentation.

Interaction with drug

Alpha-1-adrenergic blocking agents

Laboratory studies report that S. repens may act in the body like some of these medications, which may alter the effects of these medications and possibly the dose needed for treatment. Use with caution [9][10]. These drugs include prazosin, terazosin, doxazosin mesylate, tamsulosin

Interaction with other Herbs

No documentation.


No documentation.


No documentation.

Poisonous Management

No documentation.

Line drawing

No documentation.


  1. The Plant List. Ver1.1. Serenoa repens (W.Bartram) Small [homepage on the Internet]. c2013 [updated 2012 Mar 23; cited 2016 May 11]. Available from:
  2. Quattrocchi U. CRC world dictionary of medicinal and poisonous plants: Common names, scientific names, eponyms, synonyms, and etymology. Volume V R-Z. Boca Raton, Florida: CRC Press, 2012; p. 253.
  3. McKenna D, Jones K, Hughes K, Humphrey S. Botanical medicines: The desk reference for major herbal supplements. 2nd ed. New York: Routledge, 2011; p. 857.
  4. Flora of North America Editorial Committee, editor. Flora of North America: North of Mexico. Volume 22. Magnoliophyta: Alismatidae, Arecidae, Commelinidae (in part), and Zingiberidae. New York: Oxford University Press, 2000; p.105.
  5. Abe M, Ito Y, Suzuki A, Onoue S, Noguchi H, Yamada S. Isolation and pharmacological characterization ofa fatty acids from saw palmetto extract. Anal Sci. 2009;25(4):553-557.
  6. Ravenna L, Di Silverio F, Russo MA, et al. Effects of the lipidosterolic extract of Serenoa repens (permixon) on human prostatic cell lines. Prostate. 1996;29(4):219-230.
  7. Delos S, Carsol JL, Ghazarossian E, Raynaud JP, Martin PM. testosterone metabolism in primary cultures of human prostate epithelial cells and fibroblasts. J Steroid Biochem Mol Biol. 1994;48(4):347-352.
  8. Paubert-Braquet M, Richardson FO, Servent-Saez N, et al. Effect of Serenoa repens extract (permixon) on stradiol/testosterone-induced experimental prostate enlargement in the rat. Pharmacol Res. 1996;34(3-4):171-179.
  9. 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.
  10. Goepel M, Hecker U, Krege S, Rübben H, Michel MC. Saw palmetto extracts potently and non-competitively inhibit human alpha1-adrenoceptors in vitro. Prostate. 1999;38(3):208-215.
  11. Che Y, Hou S, Kang Z, Lin Q. Serenoa repens induces growth arrest and apoptosis of human multiple myeloma cells via inactivation of STAT 3 signaling. Oncol Rep. 2009;22(2):377-383.
  12. Petrangeli E, Lenti L, Buchetti B, et al. Lipido-sterolic extract of Serenoa repens (LSESr, Permixon) treatment affects human prostate cancer cell membrane organization. J Cell Physiol. 2009;219(1):69-76.
  13. 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.
  14. Baron A, Mancini M, Caldwell E, Cabrelle A, Bernardi P, Pagano F. Serenoa repens extract targets mitochondria and activates the intrinsic apoptotic pathway in human prostate cancer cells. BJU Int. 2009;103(9):1275-1283.
  15. Scholtysek C, Krukiewicz AA, Alonso JL, Sharma KP, Sharma PC, Goldmann WH. Characterizing components of the saw palmetto berry extract (spbe) on prostate cancer cell growth and traction. Biochem Biophys Res Commun. 2009;379(3):795-798.
  16. Wagner H, Proksch A, Riess-Maurer I, et al. [Immunostimulating action of polysaccharides (heteroglycans) from higher plants]. Arzneimittelforschung. 1985;35(7):1069-1075. German.
  17. Wilt TJ, Ishani A, Stark G, MacDonald R, Lau J, Mulrow C. Saw palmetto extracts for treatment of benign prostatic hyperplasia: A systematic review. JAMA. 1998;280(18):1604-1609.
  18. Hizli F, Uygur MC. A prospective study of the efficacy of Serenoa repens, tamsulosin, and Serenoa repens plus tamsulosin treatment for patients with benign prostate hyperplasia. Int Urol Nephrol. 2007;39(3):879-886.
  19. Tacklind J, MacDonald R, Rutks I, Wilt TJ. Serenoa repens for benign prostatic hyperplasia. [Cochrane review] In: The Cochrane Library, Issue 12, 2012. Art. No.: CD001423.
  20. Lopatkin N, Sivkov A, Schläfke S, Funk P, Medvedev A, Engelmann U. Efficacy and safety of a combination of Sabal and Urtica extract in lower urinary tract symptoms--long-term follow-up of a placebo-controlled, double-blind, multicenter trial. Int Urol Nephrol.2007;39(4):1137-1146.
  21. Lopatkin NA, Sivkov AV, Medvedev AA, et al. [Combined extract of Sabal palm and nettle in the treatment of patients with lower urinary tract symptoms in double blind, placebo-controlled trial]. Urologiia. Mar-Apr 2006;(2):12,14-19. Russian.
  22. 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.
  23. 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. Winter2009;3(4):323-327.
  24. Cai T, Mazzoli S, Bechi A, et al. Serenoa repens associated with Urtica dioica (ProstaMEV) and curcumin and quercitin (FlogMEV) extracts are able to improve the efficacy of prulifloxacin in bacterial prostatitis patients: Results from a prospective randomised study. Int J Antimicrob Agents. 2009;33(6):549-553.
  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(4):309-314.
  26. Plosker GL, Brogden RN. Serenoa repens (Permixon). A review of its pharmacology and therapeutic efficacy in benign prostatic hyperplasia. Drugs Aging. 1996;9(5):379-395.
  27. 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;26:247-252.
  28. Iehlé C, Délos S, Guirou O, Tate R, Raynaud JP, Martin PM. Human prostatic steriod 5-alpha-reductase isoforms--A comparative study of selective inhibitors. J Steroid Biochem Mol Biol. 1995;54(5-6):273-279.
  29. Pecoraro S, Annecchiarico A, Gambardella MC, Sepe G. Efficacy of pretreatment with Serenoa repens on bleeding associated with transurethral resection of prostate. Minerva Urol Nefrol. 2004;56(1):73-78.
  30. Braeckman J. The extract of Serenoa repens in the treatment of benign prostatic hyperplasia: A multicenter open study. Curr Ther Res. 1994;55(7):76-84.
  31. Marks LS, Partin AW, Epstein JI, et al. Effects of a saw palmetto herbal blend in men with symptomatic benign prostatic hyperplasia. J Urol. 2000;163(5):1451-1456.
  32. Gerber GS. Saw palmetto for the treatment of men with lower urinary tract symptoms. J Urol. 2000;163(5):1408-1412.
  33. Gerber GS, Zagaja GP, Bales GT, Chodak GW, Contreras BA. Saw palmetto (Serenoa repens) in men with lower urinary tract symptoms: Effects on urodynamic parameters and voiding symptoms. Urology. 1998;51(6):1003-1007.
  34. Porterfield H. UsToo PC-SPES surveys: Review of studies and update of previous survey results. Mol Urol. 2000;4(3):289-291.
  35. de la Taille A, Hayek OR, Burchardt M, Burchardt T, Katz AE. Role of herbal compounds (PC-SPES) in hormone-refractory prostate cancer: Two case reports. J Altern Complement Med. 2000;6(5):449-451.
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