Latin name Serenoa repens
Pharmacopoeial name Sabal fructus
Other names: sabal
About Saw palmetto berry
Saw palmetto is a small, low growing palm tree, native to south-eastern North America, particularly Florida. The fruits (berries) were staple food and medicine of the indigenous Floridians before European contact. They use the fruits for food and the leaf stems to make medicine baskets. They prepared an aqueous infusion of the berries as a treatment for stomach ache, dysentery, and as a diuretic and sexual tonic (1-3).
Saw palmetto berry consists of the ripe, dried fruit of serenoa repens. The berries contain fatty oil with fatty acids, esters, phytosterols and polysaccharides. The fruits are rich in triglyceride containing oils.
Saw palmetto Berry was commonly recommended for various prostatic conditions by healthcare professionals in the early 20th century and was an official drug listed in two editions of the United States pharmacopoeia (4).
Rich in fatty acids and sterols, lipophilic extracts of saw palmetto berries have been approved by both the French and German governments for the treatment of benign prostatic hyperplasia (5,6). There are numerous controlled clinical studies confirm the safe and effective use of saw palmetto preparations in treating the symptoms associated with benign prostatic hyperplasia. There is also preliminary evidence suggesting that the herb may reduce prostate enlargement; however, evidence that it may help prevent the onset of prostate cancer is lacking.
Uses of Saw palmetto berry
Benign Prostatic Hyperplasia
Many of the early clinical studies of saw palmetto for benign prostatic hyperplasia are short-term (three months or less), but they did indicate a fairly rapid response. One 28 day study of 110 patients found saw palmetto extract daily was effective in reducing painful urination, night-time urination, and retained urine in the bladder. 47 of the patients were followed for 15 to 30 months and had continued improvement (7)
Another early double-blind study was conducted on 27 patients and the authors reported a 43% increase in urinary flow rate after only 60 days of treatment with 320 mg of saw palmetto extract daily (8).
A three-month multicentre open trial of 505 patients with mild-to-moderate symptoms of benign prostatic hyperplasia was performed in 1994 and examined the effectiveness of the daily usage of a saw palmetto extract.(9) . The quality-of-life score (using the international prostate symptom score-(IPSS), urinary flow rates, residual urinary volume, and prostate size showed significant improvement in patients taking the extract after only 45 days of treatment. Serum prostate specific antigen concentration was not modified by taking the extract. Only 5% of the patients completing the study reported adverse side-effects. After 90 days, 88% of the patients and 88% of the physicians considered the therapy successful. This study indicates that the daily dose of saw palmetto is not only effective in the reduction of bhp symptoms, but also relatively low in adverse side-effects.
In an open trial, 60 patients suffering from BHP stage one and stage two were treated with a twice daily dosage of saw palmetto extract. (10). Maximum urinary flow was defined as the main outcome measure. After three months of treatment, a significant improvement of micturition parameters was observed; an increase of 24%. urinary flow rate and a reduction of both residual urine and micturition frequency.
Similarly, an open, multicentre trial involving 109 benign prostatic hyperplasia patients treated twice daily for 12 weeks with saw palmetto extract demonstrated statistically significant and also clinically relevant improvements in micturition symptoms (11).
In a six-month, double-blind, randomised equivalence study the effect of a saw palmetto extract was compared with those of a 5-alpha- reductase inhibitor in 1098 men with moderate BPH. The IPSS was used as the primary endpoint. The study found that both interventions decreased the IPSS, improved quality-of-life, and increased peak urinary flow rate. The saw palmetto extract, improved symptoms with little effect on volume and no change in PSA levels, and fared better than the 5-alpha- reductase inhibitor in a sexual function questionnaire and gave rise to less complaints of decreased libido and impotence. (12) in a three-year trial involving 309 men, saw palmetto was associated with a significant increase in urinary flow rate, and a 50% decrease in residual urinary volume. In comparison, the drug finasteride showed a 30% decrease in symptom scores over three years, but urine flow improved only slightly, and residual urinary volume was almost unchanged (13). Furthermore, 11% of finasteride patients discontinued treatment because of side-effects compared to only 1% taking saw palmetto.
Saw palmetto has therapeutic efficacy and its safety has been documented in systematic reviews and a meta-analysis of clinical studies (14). In all, 18 clinical studies , involving 2939 were reviewed in which patients had symptomatic benign prostatic hyperplasia. The medicinal preparation was made of saw palmetto alone or with other botanicals, the trials were placebo-controlled, and the trials lasted for at least 30 days. According to the authors some of the studies did not report results that allowed them to be included in the meta-analysis. They rated the treatment allocation concealment (for the purposes of blinding the studies) adequate in nine studies. 16 studies were double blinded. Study duration range from 4 to 48 weeks. Compared to placebo, saw palmetto produced lower urinary tract scores, lower frequency of nocturia, and improvement in peak urine flow. When compared to finasteride, saw palmetto users experience similar benefits, but about 90% lower incidence of adverse functions. Adverse effects were mild to infrequent and erectile dysfunction was lower when compared to finasteride.
Subsequently, two meta-analyses of all of the published and unpublished trials of only one brand of saw palmetto extract were undertaken and published (15,16). The initial analysis included 13 trials with 2794 patients. The second meta-analysis included 17 studies with 4820 patients. Nocturia decreased by 0.63 episode per night with placebo and by 1.64 episodes per night with active. Peak flow rates were improved by placebo by 1.09ml/s and by by 3.04 ml/s with active. Although the levels of improvement were small, again, the results were statistically significant. The benefits in terms of reduction of episodes of nocturia and improvement of peak urinary flow rate were similar to the earlier analyses.
Another European multicentre comparator trial was done comparing the same brand of saw palmetto berry to tamsulosin (17). The major complaint about these trials was the lack of a placebo arm, which would have clearly demonstrated the degree of clinical efficacy. Therefore, the results of these trials are difficult to interpret and must be taken with some caution. In the tamsulosin comparison trial , 704 patients were randomized after a 1-mo placebo run-in period and were treated for 1 yr. Equivalent clinical responses were demonstrated, with International Prostate Symptom Score improved by -4.4 U for each group and with peak urinary flow rates improved by 1.9 ml/s and 1.8 ml/s for the saw palmetto and tamsulosin groups, respectively. Although there was no difference in sexual function score, there was a statistically significant difference in the incidence of ejaculation disorders: 4.2% for tamsulosin and 0.6% for saw palmetto. Thus, the most widely studied saw palmetto berry product available has been shown in these meta-analyses to demonstrate a small but statistically significant improvement versus placebo. The other comparator trials show fewer sexual effects compared to other pharmaceutical agents.
Recently, a US National Institutes of Health (NIH)– sponsored, double-blind, placebo controlled study using a carbon dioxide extract of saw palmetto berry was published (18). In this study, 225 men aged >49 who had moderate to severe symptoms of BPH were treated with saw palmetto berry extract twice daily or with placebo for 1 yr. During the 1-mo placebo lead-in period, there was a small but significant improvement in AUASI score of -1.49 points compared to baseline. Both groups had further decrease in AUASI over the subsequent year of treatment (-0.68 for saw palmetto;-0.72 for placebo); however, there was no significant difference between the groups. Peak urinary flow rates improved by -0.42 ml/s for the saw palmetto–treated patients and were essentially unchanged (-0.01) ml/s for the placebo patients); again, there was no statistical difference between groups. Other parameters including prostate size, postvoid residual urinary volumes, serum PSA levels, and quality of life also were not different between the groups. The lack of efficacy noted in this trial was possibly due to the fact that the level of active ingredient was not sufficient to produce a measureable effect.
There is currently no EMEA monograph for saw palmetto
References
1. Duke, J. A. 1985, Handbook of medicinal herbs. Boca Raton. CRC Press
2. Hansel R et al. 1994 Hagers Handbuch der Pharmazeutischen Praxis Vol 6 Berlin-Heidelberg. Springer Verlag 680-687
3. Finzelberg’s Nachfolger 1999. sp saw palmetto extracts; andernach
4. Boyle W 1991 official herbs; botanical substances in the United States pharmacopoeias 1820-1990. East Palestine OH. Buckeye naturopathic press I
5. Brown, DJ. 1996 herbal prescriptions for better health. Rocklin CA. Prima Publishing 167-172
6. Tyler, VE. 1993. The honest herbal. Third edition. New York; pharmaceutical products press 285-287
7. Champault G et al. 1984 Ann Urol 18; 407-410
8. Tasca A et al 1985. Minerva Urol Nefrol 37 ; 87-91
9. Braeckman J 1994 Curr Therapeutic Res. 55 ; 776-785
10. Redeker K. 1998 Extracta Urologica 21; 23-25
11. Zeigler H et al. 1998 Jattros Uro 14; 34-43
12. Carrero J.c et al 1996. Prostate 29; 231-240
13. Bach D et al. 1997 Phytomedicine 3;309-314
14. Wilt T.J et al 1998 JAMA 280; 1604-1609
15. [8] Boyle P, Robertson C, Lowe F, Roehrborn C. Urology 2000;55:533–9.
16. [9] Boyle P, Robertson C, Lowe F, Roehrborn C. BJU Int 2004;93:751–6.
17. Debruyne F, Koch G, Boyle P, et al. Eur Urol 2002;41:497–507,
18. Bent S et al. N Engl J Med 2006;354:557–66.
