Labetalol, Beta Blockers, and Acute Deterioration of Chronic Airway Obstruction

The effects on lung function of labetalol (a combined α and β adrenergic receptor blocker) and three β adrenergic receptor blockers (propranolol, atenolol, metoprolol) have been assessed in patients with chronic airflow obstruction using a doubleblind trial.With the dosages used, all drugs produced an equivalent fall of blood pressure.Propranolol was the only drug that significantly increased airways obstruction (FEV1, specific airways resistance). Following salbutamol, labetalol−was associated with a significantly greater improvement of airflow than either propranolol or metoprolol.On these acute studies, the order of preference for β blocking drugs in management of hypertension in patients with obstructive airways disease, would be labetalol, (atenolol) or (metoprolol) and then propranolol.