Saw palmetto (Serenoa repens)
Although several small studies have suggested modest benefit of saw palmetto for treating symptoms of BPH, a large study evaluating high doses of saw palmetto and a Cochrane review found that saw palmetto was not more effective than placebo for treatment of urinary symptoms related to BPH. However, a recent systematic review and meta-analysis found that Serenoa repens had the same effect as tamsulosin in treating BPH in terms of International Prostate Symptom Score, quality of life, maximum flow rate, postvoid residual volume, and prostate-specific antigen, with the exception of prostate volume. A single randomized controlled trial showed combination therapy of saw palmetto plus lycopene, selenium, and tamsulosin was more effective than single therapies alone.
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Urtica dioica
There is some limited evidence that Urtica dioica may improve some symptoms of BPH, including lower urinary tract symptoms. There is also some limited evidence that a combination of Urtica dioica and saw palmetto (Serenoa repens) may be efficacious for lower urinary tract symptoms associated with BPH.
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