Across 3 studies, 2 reported neutral effects (small effect size) and 1 reported a beneficial effect (moderate effect size). The evidence is mixed and limited, with the most recent review (2023) noting only modest effectiveness and a 2016 review finding no significant benefit in larger, more rigorous studies. No consistent dose or duration could be identified.
Caveats: Evidence base is small (only 3 studies) — conclusions should be considered preliminary. Many of the included studies did not reach statistical significance — effect may be smaller than the predominant direction suggests. All three studies are literature reviews, not primary clinical trials. The 2016 review noted that more recent, larger, and more soundly constructed studies found no significant benefit for phytotherapy in BPH, casting doubt on the positive findings from older reviews.
Generally, though, all treatments were tolerated well with minimal side effects.
from: Role of Phytotherapy in the Management of BPH: A Summary of the Literature.For most of the reviewed substances, only modest effectiveness was reported.
more recent, larger and more soundly constructed studies found no significant benefit for the use of phytotherapy in the treatment of BPH
This articles review the mode of action, the efficacy, and the safety, including herb-drug interactions of the most common botanicals (Serenoa repens, Pygeum africanum, Urtica dioica, and Cucurbita pepo) and nutraceuticals (isoflavones, lycopene, selenium, and β-Sitosterol) in controlling the lower urinary tract symptoms associated to BPH.