Abstract
Pharmacotherapy for the treatment of BPH is currently being targeted to relax prostate smooth muscle (alpha blockade) and decrease prostate volume (androgen suppression). The objective of the present study was to determine the relative efficacy of terazosin vs. terazosin and flutamide (combination therapy) for the treatment of symptomatic BPH. Twenty-nine males with symptomatic BPH were enrolled into this 6-month open label study. The entry criteria included peak urinary flow rate between 4-15 ml/sec, a total Boyarsky symptom score greater than 7, and postvoid residual less than 300 ml. The daily dosage of terazosin was titrated to 5 mg over a 2-week interval. A 750 mg daily dosage of flutamide was added following 1 month of terazosin monotherapy. The dosages were lowered if significant adverse events developed. Efficacy assessments were performed at 1 month (terazosin alone), 6 months (combination therapy), or at the time of early withdrawal from the study. The efficacy of combination therapy was evaluable in 24 patients receiving combination therapy. At one month, the mean peak urinary flow rate and mean total Boyarsky symptom score improved 38% and 56% relative to baseline, respectively. The present study confirmed the previously observed efficacy and safety of terazosin for BPH. The addition of flutamide did not result in statistically significant improvements in the peak urinary flow rate or total Boyarsky symptom score. The adverse events related to flutamide resulted in 16 dose reductions and 14 premature withdrawals. The role of combination therapy will require a randomized placebo controlled study sufficiently powerful to identify clinically and statistically significant improvements in objective outcome parameters relative to the monotherapies.