Effect of tamsulosin versus prazosin on clinical and urodynamic parameters in women with voiding difficulty: a randomized clinical trial

OBJECTIVE To compare the effects of tamsulosin and prazosin on clinical and urodynamic parameters in women with voiding dysfunction. METHODS Forty women aged 20-65 years with a clinical diagnosis of voiding dysfunction were blindly randomized to two equal groups for treatment with tamsulosin 0.4 mg or 1-2 mg of prazosin daily. Symptom assessment with the American Urological Association Symptom Score (AUASS) and urodynamic evaluation was performed initially and after three months of treatment. Patient satisfaction was evaluated and severe adverse drug effects recorded. Statistical analysis was carried out using the Student's t-test and Mann-Whitney U test. RESULTS Although AUASS improved in both groups, the rate of improvement was larger in the tamsulosin group. Urodynamic parameters improved but did not normalize in both groups. Adverse side effects from medication in the prazosin group were more common than in the tamsulosin group. Most of the patients in the tamsulosin group (80%) were satisfied with their treatment compared with those in the prazosin group (45%). CONCLUSION Tamsulosin and prazosin are both effective in palliating symptoms of women with voiding dysfunction and improving their urodynamic parameters. Tamsulosin may be the preferred drug to prescribe because of its more amenable side effect profile and greater patient satisfaction.