Tamsulosin for treating lower urinary tract symptoms compatible with benign prostatic obstruction: A systematic review of efficacy and adverse effects

Purpose: We systematically reviewed the effectiveness and adverse effects of tamsulosin for lower urinary tract symptoms compatible with benign prostatic obstruction. Materials and Methods: Studies were included in analysis when they involved a randomized trial of at least 1 month in duration, men with lower urinary tract symptoms and a comparison of tamsulosin with placebo or an active control. Study, patient and outcome data were extracted onto standard forms using a prospective protocol. Results: Of the series 13 involving 3,418 men with a mean age of 64 years met our inclusion criteria. Study duration was 4 to 26 weeks. Baseline symptom scores and flow rates showed moderate lower urinary tract symptoms. Tamsulosin improved symptoms and peak urine flow compared with placebo. The weighted mean difference in the mean change from baseline for the Boyarsky symptom score for 0.4 and 0.8 mg. tamsulosin versus placebo was -1.1 (95% confidence interval [CI] -1.49 to -0.72 or 12% improvement) and -1.6 points (95% CI -2.3 to -1.0 or 16% improvement), respectively. The weighted mean difference in the mean change from baseline in peak urine flow was 1.1 (95% CI 0.59 to 1.51) and 1.1 ml. per second (95% CI 0.65 to 1.48) for 0.4 and 0.8 mg., respectively. The 0.2 to 0.4 mg. tamsulosin dose was as effective as other α-antagonists for improving symptoms and the flow rate, although the doses of all α-antagonists evaluated may not have been optimal. Treatment withdrawals and adverse effects increased markedly as the tamsulosin dose increased. Conclusions: Tamsulosin improves lower urinary tract symptoms and flow. Its effectiveness was similar to that of other α-antagonists, increasing slightly at higher doses. Adverse effects were generally mild but the incidence, including treatment withdrawals, increased substantially at higher doses.