Across 3 studies, 2 high-quality studies (a systematic review and a meta-analysis) found no significant effect of saw palmetto (Serenoa repens) on nocturia compared to placebo, while a single low-quality review reported a small beneficial effect. The evidence is predominantly neutral, with small effect sizes in all studies. The most-studied dose range is 640–960 mg/day in men with symptomatic benign prostatic hyperplasia (BPH).
Caveats: Evidence base is small (only 3 studies) — conclusions should be considered preliminary. The two highest-quality studies did not find a statistically significant benefit, while the only study reporting a benefit was a low-quality narrative review. The overall evidence does not support saw palmetto for reducing nocturia.
No significant difference between SR and placebo (MD -1.22 cc, 95% CI -3.91 to 1.47) for prostate size; harms outcome not specifically quantified.
from: Serenoa repens for benign prostatic hyperplasia.Adverse events of Serenoa repens extracts were few and mild, and incidences were not statistically significantly different vs placebo.
from: Serenoa repens monotherapy for benign prostatic hyperplasia (BPH): an updated Cochrane sysAdverse events were generally mild and comparable to placebo.
from: Serenoa repens monotherapy for benign prostatic hyperplasia (BPH): an updated Cochrane sysThe main outcome measure for harms was the number of men reporting side effects.
from: Serenoa repens for benign prostatic hyperplasia.Long-term, Serenoa repens therapy was no better than placebo in improving nocturia in one high-quality study (P= 0.19)
versus placebo, SR did not significantly decrease nightly urination on the AUA Nocturia scale (range zero to five) at 72 weeks follow-up (one-sided P = 0.19).
Recent meta-analyses found the effectiveness of Serenoa repens similar or inferior of that of finasteride and tamsulosin but clearly higher than that of placebo in the treatment of mild and moderate low urinary tract symptoms (LUTS), nocturia and discomfort.