Role of alpha-adrenergic blockers in the treatment of benign prostatic hyperplasia.

The dynamic component of infravesical obstruction in men with symptomatic benign prostatic hyperplasia (BPH) is determined by alpha 1-adrenoceptor-mediated contractions of the prostatic capsule, prostate adenoma, and bladder neck. Since alpha 1-adrenoceptors are sparse in the bladder, medical therapy aimed at blocking the alpha receptor will relieve bladder outlet obstruction without inhibiting bladder function. Numerous clinical studies have evaluated the use of various alpha blockers for the treatment of BPH. Although the majority of these trials involved limited numbers of patients treated for only short periods, their results have consistently shown that alpha blockers improve urinary flow rates. Adverse reactions appear to be more frequent and more serious with the use of nonselective alpha blockers than with selective alpha 1 blockers, such as terazosin or prazosin. Terazosin offers the additional advantage of once-daily dosing. The common association of hypertension, hyperlipidemia, and symptomatic BPH in the aging male population may provide further impetus for initiating treatment with alpha blockers because alpha blockers are effective antihypertensive agents and may favorably alter lipid profiles.