Clinical Question
Does saw palmetto (Serenoa repens) reduce symptoms associated with benign prostatic hyperplasia (BPH)?
Evidence-Based Answer
Saw palmetto, alone or in combination with other phytotherapeutic agents, does not improve urologic symptoms or quality of life in the short term (3 to 6 months) or long term (12 to 17 months). Also, it does not cause significant adverse events.1 (Strength of Recommendation: A, consistent, good-quality patient-oriented evidence.)
Practice Pointers
BPH-related symptoms of urologic obstruction and irritation affect about one-fourth of men in their 50s, one-third of men in their 60s, and one-half of men 80 years or older.2 Using plants and herbs (phytotherapy) for this condition is common worldwide. Saw palmetto is one of the most commonly used phytotherapeutic agents. The authors of this Cochrane review sought to determine whether saw palmetto, alone or in combination with other phytotherapeutic agents, improves urologic symptoms due to BPH.
This Cochrane review included 27 randomized controlled trials with 4,656 participants.1 In the review, 19 trials compared saw palmetto to placebo, and eight trials compared the combination of saw palmetto and other phytotherapeutic agents to placebo. Almost all studies used a saw palmetto dosage of 320 mg per day. Other agents used in combination with saw palmetto included pumpkin seed oil, lycopene, and sabal and urtica extract. Most studies included participants who were older than 50 years (mean age = 52 to 68 years) with moderate urologic symptoms (International Prostate Symptom Score [IPSS] = 8 to 19). For urologic symptoms, the authors considered an improvement of 3 points on the IPSS as the minimal clinically important difference to determine effectiveness. The authors used the final question on the IPSS to analyze quality of life and considered an improvement of 0.5 as the minimal clinically important difference to determine effectiveness.
At short-term follow-up (3 to 6 months), when compared with use of placebo, saw palmetto treatment alone did not improve urologic symptoms (IPSS range = 0 to 35; mean difference [MD] = −0.90; 95% CI, −1.74 to −0.07) or quality of life (IPSS range = 0 to 6; MD = −0.20; 95% CI, −0.40 to −0.00). Similarly, at longer-term follow-up (12 to 17 months), no significant improvements in urologic symptoms or quality of life were noted. Saw palmetto did not cause more adverse events throughout the studies (risk ratio = 1.01; 95% CI, 0.77 to 1.31). In combination with other therapeutic agents, saw palmetto resulted in little to no difference in urologic symptoms, quality of life, or adverse events. Findings were consistent across most studies. The few studies that indicated some improvement in urologic symptoms and quality of life were industry funded, used a very small sample size, or did not demonstrate a clinically relevant improvement based on the predefined minimal clinically important difference.
When treating patients with symptoms of BPH, the National Institute for Health and Care Excellence recommends not offering phytotherapy.3 The 2021 American Urological Association guideline does not include phytotherapy in its treatment algorithm, and the previous version recommended against phytotherapeutic agents.4 The 2023 European Association of Urology guidelines recommend using saw palmetto in patients who want to avoid potential adverse events associated with more effective medicines (weak recommendation) while informing the patient that the magnitude of effectiveness may be modest (strong recommendation). These guidelines did not include findings from this Cochrane review.5
The practice recommendations in this activity are available at https://www.cochrane.org/CD001423.
The views expressed in this article are those of the authors and do not necessarily reflect the official policy or position of the U.S. Department of the Navy, the U.S. Department of Defense, or the U.S. government.
