Finasteride in the treatment of benign prostatic hyperplasia

Finasteride is an enzyme inhibitor which blocks the conversion of testosterone by 5 alpha-reductase to dihydrotestosterone, the active androgenic metabolite in the prostate. In a double-blind, placebo-controlled study, 707 patients with moderately symptomatic BPH were treated for 2 years. The study confirmed that treatment significantly improved symptoms, reduced prostate size and increased urine flow rate. Side effects were usually mild. The authors find that finasteride can reverse the natural progression of BPH.