[Clinical study of bunazosin hydrochloride, an alpha 1-adrenergic blocker, in benign prostatic obstruction and...

A newly developed alpha 1-adrenergic blocker, bunazosin hydrochloride (Detantol, Eisai) was clinically investigated in 17 patients with benign prostatic obstruction and 18 patients with neurogenic bladder dysfunction. Subjective symptoms improved in 11 of the 17 cases (64.7%) with prostatic obstruction and in 4 of the 10 cases (40%) with neurogenic bladder dysfunction. Dose-dependent subjective improvement was observed with dosages of 3 to 9 mg/day. A dosage of 12 mg/day did not improve subjective symptoms more than did the 9 mg/day dose. In prostatic obstruction, 7 of the 10 objective parameters improved significantly. However, for neurogenic bladder dysfunction, only two parameters improved significantly. Improvements in objective findings were generally dose-dependent in cases of prostatic obstruction, but not in neurogenic bladder dysfunction. Mild side effects, none of them serious, were reported in 9 of the total 35 cases (26%). They generally consisted of dizziness, nasal obstruction and headache. Comprehensive improvement, i.e., improvement of both subjective symptoms and objective parameters, occurred in 11 of the 17 cases (64.7%) of prostatic obstruction and 6 of the 18 cases (33.3%) of neurogenic bladder dysfunction.