Are all alpha-blockers created equal? An update.

alpha-Receptor blockers, used to treat lower urinary tract symptoms, exert effects on areas of the body other than the prostate where alpha-receptors are located, including the blood vessels and the central nervous system. alpha-Receptors in the central and peripheral nervous system may be involved in bladder activation. alpha(1a)-Receptors are the appropriate target in men with obstructive symptoms, although alpha(1d)-receptors may also be important in patients with irritative symptoms. There is conflicting evidence about the selectivity of alpha-blockers. Clinical trials of these agents do not necessarily reflect results observed in animal and laboratory studies on uroselectivity. The few published comparator studies of alpha-blockers indicate similar efficacies, although side-effect profiles differ somewhat. Randomized, controlled studies of different alpha-blockers with sufficient power to detect differences in side effects between agents are needed.