Secondary bladder neck obstruction in patients with urethral valves: Treatment with phenoxybenzamine.

Two cases are reported of functionally significant bladder neck obstruction following urethral valve fulguration which resulted in inability to void. Both patients responded to the administration of phenoxybenzamine, an alpha-adrenergic blocking agent. Treatment of patients with suspected bladder neck obstruction with this agent provides a reversible method of decreasing urethral resistance without the potentially harmful effects of surgical bladder neck revision.