First dose efficacy of alfuzosin once daily in men with symptomatic benign prostatic hyperplasia

Objectives. To evaluate the onset of action of alfuzosin once daily (OD) as determined by uroflowmetry early after initial dosing. Alfuzosin OD is an extended-release formulation of a uroselective, alpha₁- adrenoreceptor-blocking agent (alpha-blocker) used in the treatment of lower urinary tract symptoms due to benign prostatic hyperplasia. Methods. This was a randomized, placebo-controlled, two-way Latin square crossover study. Forty-nine patients were selected for this study on the basis of their symptomatic improvement during previous treatment with alpha-blockers and significant decreases in urinary flow rate when that treatment was withdrawn. Results. Our analysis showed that significant increases in the maximal urinary flow rate (Qmax) in 34 assessable patients occurred as soon as 8 hours after the initial dose of medication and persisted for at least 4 days. The ΔQmax for alfuzosin 10 mg OD was 3.2 mL/s and for placebo it was 1.1 mL/s. The difference of means for the assessable population was 2.1 (95% confidence interval 0.8 to 3.4, P = 0.002). The overall incidence of adverse events was low. Only dizziness, experienced by 3 patients treated with alfuzosin compared with 1 patient treated with placebo, appeared to be related to the study drug. Conclusions. Together, our findings suggest that alfuzosin OD exhibits a urodynamically measurable effect on bladder outlet obstruction due to benign prostatic hyperplasia in men with lower urinary tract symptoms within hours of the first administration.