Morning vs evening dosing with doxazosin in benign prostatic hyperplasia: efficacy and safety.

Three hundred and fifty-three patients with symptomatic benign prostatic hyperplasia were randomized to doxazosin or placebo, with morning or evening dosing, to compare the effect of dosing time on the efficacy and safety of doxazosin treatment. After 24 weeks of treatment, the mean International Prostate Symptom Score had decreased by 6.8 units in the doxazosin group compared with 4.5 units in the placebo group (P=0.003). Improvements in Q(max) of 2.03 ml/s and 0.30 ml/s were seen for the doxazosin and the placebo groups, respectively (P<0.001). No differences in efficacy or safety between the morning- and evening-dosed subgroups were observed. Doxazosin was significantly more effective than placebo at improving symptoms of BPH and urinary flow rates at endpoint, and was well tolerated. The time of dosing did not appear to influence the efficacy or safety of doxazosin, suggesting that there is no need to restrict administration of doxazosin to the evening in BPH patients.