Saw palmetto extract

Saw palmetto extract is an extract of the fruit of Serenoa repens. It is rich in fatty acids and phytosterols. It has been used in traditional, eclectic, and alternative medicine to treat a variety of conditions, most notably benign prostatic hyperplasia (BPH). Reviews of clinical trials, including those conducted by the National Center for Complementary and Alternative Medicine, found the extract to be no more effective than placebo for BPH.[1]

Medicinal use

Saw palmetto is used in several forms of traditional herbal medicine. American Indians used the fruit for food and to treat a variety of urinary and reproductive system problems. The Mayans drank it as a tonic, and the Seminoles used the berries as an expectorant and antiseptic.[2]

Crude saw palmetto extract was used by European/American medical practitioners for at least 200 years for various conditions, including asthenia (weakness), recovery from major illness, and urogenital problems. The eclectic medicine practitioner H. W. Felter wrote of it, "Saw palmetto is a nerve sedative, expectorant, and a nutritive tonic, acting kindly upon the digestive tract...Its most direct action appears to be upon the reproductive organs when undergoing waste of tissue..."[3]

King's American Dispensatory (1898) says of the extract:

It is also an expectorant, and controls irritation of mucous tissues. It has proved useful in irritative cough, chronic bronchial coughs, whooping-cough, laryngitis, acute and chronic, acute catarrh, asthma, tubercular laryngitis, and in the cough of phthisis pulmonalis. Upon the digestive organs it acts kindly, improving the appetite, digestion, and assimilation. However, its most pronounced effects appear to be those exerted upon the urino-genital tracts of both male and female, and upon all the organs concerned in reproduction. It is said to enlarge wasted organs, as the breasts, ovaries, and testicles, while the paradoxical claim is also made that it reduces hypertrophy of the prostate. Possibly this may be explained by claiming that it tends toward the production of a normal condition, reducing parts when unhealthily enlarged, and increasing them when atrophied.[4]

Saw palmetto extract is the most popular herbal treatment for benign prostatic hyperplasia,[5] a common condition in older men. Early research indicated that the extract is well-tolerated and suggested "mild to moderate improvement in urinary symptoms and flow measures."[5][6] Later trials of higher methodological quality indicated no difference from placebo.[7][8] Questions of adequate blinding and delivery of any active ingredients remain.[9] The latest Cochrane Database review (2009) concludes that "Serenoa repens was not more effective than placebo for treatment of urinary symptoms consistent with BPH."[1]

A 2011 study published in JAMA (The Journal of the American Medical Association) reported on a double-blind study that eleven North American clinics conducted on 369 men. The study found that saw palmetto fruit extract failed to reduce urinary tract symptoms more than placebo.[10] Men in the experimental group experienced a 2.20 point drop in their American Urological Assn. Symptom Index (AUASI) score. However, men in the placebo group saw a 2.99 point drop. The Los Angeles Times reports, “42.6% of the men in the extract group saw their AUASI scores fall by at least three points; 44.2% of the men in the placebo group saw the same degree of benefit.” The study was funded by several offices within the NIH, including the National Center for Complementary and Alternative Medicine.”[11]

Inhibition of both forms of 5-alpha-reductase with no reduction in cellular capacity to secrete prostate-specific antigen is indicated.[12][13][14][15] Other proposals for mechanisms of action include interfering with dihydrotestosterone binding to the androgen receptor, relaxing smooth muscle tissue similarly to alpha antagonist drugs, and acting as a phytoestrogen.[16][17]

Limited in vitro and animal model studies have investigated potential for use in the treatment of cancer.[12][18][19] However, according to the American Cancer Society, "available scientific studies do not support claims that saw palmetto can prevent or treat prostate cancer in humans".[20]

Saw palmetto extract has been suggested as a potential treatment for male pattern baldness.[21]

Side Effects

Few side effects or allergic reactions are associated with saw palmetto extract use. The most common are gastrointestinal, some of which may be reduced by taking the extract with food. Use may increase the risk of bleeding or affect sex hormones, and concurrent use of other drugs with similar action should be avoided.[21]

Beta-sitosterol, a chemical present in saw palmetto extract, is chemically similar to cholesterol. High levels of sitosterol concentrations in blood have correlated with increased severity of heart disease in men who previously suffered heart attacks. However, this is a preliminary finding and more research is needed before any conclusions can be made.[22]

Precautions and contraindications

Children

The use of saw palmetto extract is not recommended in children under 12 years old because it may affect the metabolism of androgen and estrogen hormones.[23] In a case report, an 11 year old girl experienced hot flashes after using saw palmetto extract. The symptom went away after she stopped taking the extract.[24]

Pregnancy and lactation

Saw palmetto extract should not be used during pregnancy.[23] The effects of saw palmetto extract on androgen and estrogen metabolism can potentially impair fetal genital development.[25] Saw palmetto extract should also be avoided during breastfeeding due to a lack of available information.[25]

Surgery

Saw palmetto extract can significantly slow down blood clotting, leading to increased bleeding time before and after surgery.[26] In a case report, a patient taking saw palmetto had increased bleeding time during surgery. The bleeding time returned to normal after he stopped taking the herb.[27] It is recommended that the use of saw palmetto extract be stopped at least two weeks before a scheduled surgery.[26]

Interactions

Saw palmetto extract may decrease the effectiveness of estrogen products by reducing estrogen levels in the body via its antiestrogenic effects.[25] It can interfere with the use of birth control pills that contain estrogen as an active ingredient. As a result, it is recommended that an additional form of birth control, such as a condom, be used to prevent pregnancy in patients taking birth control pills with saw palmetto extract. In addition, saw palmetto extract can also interfere with hormone replacement therapy by reducing the effectiveness of estrogen pills.[26] Therefore, the combination of saw palmetto extract with estrogen products should be used with caution.[25]

When used in combination with an anticoagulant or antiplatelet drug, saw palmetto extract can increase the risk of bleeding by enhancing the anticoagulation or antiplatelet effects.[26] Some examples of anticoagulant and antiplatelet drugs include aspirin, clopidogrel, nonsteroidal anti-inflammatory drugs (NSAIDs) and warfarin. Therefore, the combination of saw palmetto extract with anticoagulant or antiplatelet drugs should be used with caution.[25]

See also

References

  1. ↑ 1.0 1.1 Tacklind, J; MacDonald, R; Rutks, I; Wilt, TJ (2009). Tacklind, James, ed. "Serenoa repens for benign prostatic hyperplasia". Cochrane database of systematic reviews (Online) (2): CD001423. doi:10.1002/14651858.CD001423.pub2. PMC 3090655. PMID 19370565.
  2. ↑ "Saw palmetto (Serenoa repens [Bartram] Small)]". Mayo Clinic. Retrieved 2011-12-15.
  3. ↑ Felter's complete text
  4. ↑ King's American Dispensatory 1898
  5. ↑ 5.0 5.1 Markowitz JS, Donovan JL, Devane CL et al. (December 2003). "Multiple doses of saw palmetto (Serenoa repens) did not alter cytochrome P450 2D6 and 3A4 activity in normal volunteers". Clin. Pharmacol. Ther. 74 (6): 536–42. doi:10.1016/j.clpt.2003.08.010. PMID 14663456.
  6. ↑ Wilt T, Ishani A, Mac Donald R (2002). Tacklind, James, ed. "Serenoa repens for benign prostatic hyperplasia". Cochrane Database Syst Rev (3): CD001423. doi:10.1002/14651858.CD001423. PMID 12137626.
  7. ↑ Bent S, Kane C, Shinohara K et al. (February 2006). "Saw palmetto for benign prostatic hyperplasia". N. Engl. J. Med. 354 (6): 557–66. doi:10.1056/NEJMoa053085. PMID 16467543.
  8. ↑ Dedhia RC, McVary KT (June 2008). "Phytotherapy for lower urinary tract symptoms secondary to benign prostatic hyperplasia". J. Urol. 179 (6): 2119–25. doi:10.1016/j.juro.2008.01.094. PMID 18423748.
  9. ↑ Allison Aubrey (9 February 2006). Morning Edition: Study Casts Doubt on Saw Palmetto as Prostate Remedy (Audio recording). National Public Radio.
  10. ↑ "Effect of Increasing Doses of Saw Palmetto Extract on Lower Urinary Tract Symptoms". Journal of the American Medical Association. Retrieved 2011-10-08.
  11. ↑ "Saw palmetto extract likely won't relieve enlarged prostate symptoms". Los Angeles Times. 27 September 2011. Retrieved 2011-10-08.
  12. ↑ 12.0 12.1 Wadsworth TL, Worstell TR, Greenberg NM, Roselli CE (May 2007). "Effects of dietary saw palmetto on the prostate of transgenic adenocarcinoma of the mouse prostate model (TRAMP)". The Prostate 67 (6): 661–73. doi:10.1002/pros.20552. PMID 17342743.
  13. ↑ Scaglione F, Lucini V, Pannacci M, Caronno A, Leone C (2008). "Comparison of the potency of different brands of Serenoa repens extract on 5alpha-reductase types I and II in prostatic co-cultured epithelial and fibroblast cells". Pharmacology 82 (4): 270–5. doi:10.1159/000161128. PMID 18849646.
  14. ↑ Abe M, Ito Y, Oyunzul L, Oki-Fujino T, Yamada S (April 2009). "Pharmacologically relevant receptor binding characteristics and 5alpha-reductase inhibitory activity of free Fatty acids contained in saw palmetto extract". Biological & Pharmaceutical Bulletin 32 (4): 646–50. doi:10.1248/bpb.32.646. PMID 19336899.
  15. ↑ Habib FK, Ross M, Ho CK, Lyons V, Chapman K (March 2005). "Serenoa repens (Permixon) inhibits the 5alpha-reductase activity of human prostate cancer cell lines without interfering with PSA expression". International Journal of Cancer 114 (2): 190–4. doi:10.1002/ijc.20701. PMID 15543614.
  16. ↑ Di Silverio F, Monti S, Sciarra A et al. (October 1998). "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". The Prostate 37 (2): 77–83. doi:10.1002/(SICI)1097-0045(19981001)37:2<77::AID-PROS3>3.0.CO;2-I. PMID 9759701.
  17. ↑ Plosker GL, Brogden RN (November 1996). "Serenoa repens (Permixon). A review of its pharmacology and therapeutic efficacy in benign prostatic hyperplasia". Drugs & Aging 9 (5): 379–95. doi:10.2165/00002512-199609050-00008. PMID 8922564.
  18. ↑ Scholtysek C, Krukiewicz AA, Alonso JL, Sharma KP, Sharma PC, Goldmann WH (February 2009). "Characterizing components of the Saw Palmetto Berry Extract (SPBE) on prostate cancer cell growth and traction". Biochemical and Biophysical Research Communications 379 (3): 795–8. doi:10.1016/j.bbrc.2008.11.114. PMID 19059205.
  19. ↑ Anderson ML (2005). "A preliminary investigation of the enzymatic inhibition of 5alpha-reduction and growth of prostatic carcinoma cell line LNCap-FGC by natural astaxanthin and Saw Palmetto lipid extract in vitro". Journal of Herbal Pharmacotherapy 5 (1): 17–26. doi:10.1300/J157v05n01_03. PMID 16093232.
  20. ↑ "Saw Palmetto". American Cancer Society. 28 November 2008. Retrieved 13 September 2013.
  21. ↑ 21.0 21.1 "Saw Palmetto". MedlinePlus (National Library of Medicine). 2008-02-01. Retrieved 2009-03-16.
  22. ↑ Assmann G, Cullen P, Erbey J, Ramey DR, Kannenberg F, Schulte H (January 2006). "Plasma sitosterol elevations are associated with increased incidence of coronary events in men: results of a nested case-control analysis of the Prospective Cardiovascular Münster (PROCAM) study". Nutrition, Metabolism, and Cardiovascular Diseases : NMCD 16 (1): 13–21. doi:10.1016/j.numecd.2005.04.001. PMID 16399487.
  23. ↑ 23.0 23.1 "Fructus Serenoae Repentis". WHO Monographs on Selected Medicinal Plants. World Health Organization. Retrieved 29 October 2014.
  24. ↑ Miroddi, M; Carni, A; Mannucci, C; Moleti, M; Navarra, M; Calapai, G (Nov 2012). "Hot flashes in a young girl: a wake-up call concerning Serenoa repens use in children". Pediatrics. 130 (5): 1374-6. doi:10.1542/peds.2011-2679. PMID 23027164.
  25. ↑ 25.0 25.1 25.2 25.3 25.4 "Saw Palmetto". Natural Standard: The Authority on Integrative Medicine. Natural Standard. Retrieved 29 October 2014.
  26. ↑ 26.0 26.1 26.2 26.3 "Saw Palmetto". MedlinePlus: Trusted Health Information for You. Therapeutic Research Faculty. Retrieved 29 October 2014.
  27. ↑ Cheema, P; El-Mefty, O; Jazieh, AR (Aug 2001). "Intraoperative haemorrhage associated with the use of extract of Saw Palmetto herb: a case report and review of literature". J Intern Med. 250 (2): 167–9. doi:10.1046/j.1365-2796.2001.00851.x. PMID 11489067.

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