Medical Management of BPH: Role of Plant Extracts

ObjectivesSince decades plant extracts belong to the most popular drugs for lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH)/benign prostatic enlargement (BPE). Herein we review biological mechanisms, the placebo effect, results of clinical trials, the role of meta-analyses and guideline recommendations.MethodsReview of the literature with particular reference to long-term (study period ≥6 months) controlled trials and of BPH-guideline recommendations.ResultsOnly few of the large number of available studies meet the criteria defined by the WHO-BPH consensus conference. The few, placebo-controlled, long-term (study period ≥6 months) studies suggest a positive effect of some extracts (saw palmetto, ß-sitosterol, urtica, saw palmetto/urtica combination) on LUTS, an effect on uroflow, post-void residual volume, prostate volume and PSA was not consistently demonstrable. Randomised trials against active comparators (α1-blocker, 5α-reductase inhibitors) are difficult to interpret. Due to the lack of prospective studies, several meta-analyses have been published that can not replace prospective studies according to WHO-BPH recommendations. None of the BPH-guidelines currently recommends plant extracts, yet universally conclude that this is an interesting approach.ConclusionsFurther prospective studies according to WHO-standards are required to reliably determine the role of plant extracts in contemporary LUTS-management.