Cochrane corner: beta-blockers for hypertension

Abstract

Beta-blockers refer to an assorted group of medications that block the action of endogenous catecholamines on beta-adrenergic receptors.1 The ß1 and ß2 receptorsare the primary beta-adrenergic receptors in the human cardiovascular system. Beta- blockers differ in their ß1/ ß2-receptor selectivity and vasodilatory properties. Based on this diversity, beta-blockers have been categorised into first, second and third generation. First-generation beta-blockers, also referred to as non-selective blockers, possess equal affinity for ß1 and ß2 receptors. Second-generation (or selective) beta-blockers exercise more affinity for ß1 than ß2 receptors. Neither of these traditional beta-blockers has vasodilatory properties, which is an intrinsic characteristic of third-generation beta-blockers.