RESUMO
Beta-adrenergic blocking agents are commonly used for the management of hypertension, cardiac arrhythmias, and angina pectoris; several of these agents are now available for clinical use (1-5). A significant side effect of these agents in patients experiencing reversible airway obstruction is that they block the effects of beta-adrenergic agonists and can precipitate or worsen bronchospasm (6-8). Labetalol, a new adrenergic antagonist with both alpha- and beta-adrenergic blocking effects, has been shown to have certain advantages for the management of hypertension and is widely used for this purpose in many countries (9). To evaluate its effects on airway resistance in patients with obstructive lung disease, the authors conducted two separate clinical studies. This article summarizes the results of these trials.
