29-week doxazosin treatment in patients with symptomatic benign prostatic hyperplasia. A double-blind placebo-controlled study.
In a placebo-controlled study, the safety and efficacy of the selective alpha 1-adrenoceptor-blocking agent doxazosin 4 mg once daily in the symptomatic treatment of benign prostatic hyperplasia (BPH) were evaluated. One hundred patients were primarily included in a 9-weeks study, and after this 75 patients accepted to continue in the present 20 weeks extension. Of the patients in the doxazosin-group (DG) 61% reported overall improvement against 53% in the placebo-group (PG)--(p = 0.56). In the DG, 49% of obstructive symptoms were improved compared to 27% in the PG (p < 0.01), and a reduction of 60% of irritative symptoms was found in the DG against 36% in the PG (p < 0.01). Daytime frequency was reduced by median 1.5 in the DG and remained unchanged in the PG (p < 0.01). Nocturia was reduced by median 1 and 0.5 respectively (p = 0.06). Maximum urinary flow rate (MFR) was improved by median 1.5 ml/s in the DG, while it deteriorated by median 0.5 ml/s in the PG (p < 0.05), Considering postvoid residual urine volume, cystometry variables (first sensation and bladder capacity), changes in sexual function and adverse events there was no difference between the two groups. In conclusion, doxazosin 4 mg once daily in long-term treatment of patients with BPH reduces both obstructive and irritative symptoms, daytime voiding frequency and although only slightly, significantly augments MFR without interference with sexual function and without other serious adverse effects.