Therapeutic effects of finasteride in benign prostatic hyperplasia: a randomized double-blind controlled trial.

The clinical effects of finasteride, a 5 alpha-reductase inhibitor, in patients with benign prostatic hyperplasia (BPH) were evaluated in a double-blind, placebo-controlled study. Forty-six patients with symptomatic BPH were randomly assigned to 2 groups, the finasteride group and the placebo group. The finasteride group received 5 mg of finasteride daily for 6 months. Prostate volume, urinary flow, urinary symptoms, serum prostate-specific antigen (PSA) and adverse events were determined before and after treatment. After 6 months of treatment the patients treated with 5 mg of finasteride per day had a 30% decrease in their total urinary symptom score, a 14% decrease in prostate volume and a 0.9 ng/dL decrease of PSA. Their maximal urinary flow rate increased by 1.42 mL per second and the mean urinary flow rate increased by 0.64 mL per second. The patients given placebo showed no significant changes in their prostate volume, serum PSA and maximal and mean urinary flow rate. However, the symptom scores in the placebo group also decreased significantly. When compared with the placebo group, those in the finasteride group had significantly lower prostate volume, serum PSA, maximal urinary flow rate and urinary symptoms, but not mean urinary flow rate. The frequency of adverse events was low in both the finasteride and placebo groups. These results show that finasteride may be an effective and safe alternative for the treatment of patients with BPH.