A double-blind crossover clinical trial of labetalol and propranolol in patients of essential hypertension.

The efficacy and safety of labetalol was compared in a double-blind crossover design with propranolol in 27 patients suffering from essential hypertension with a supine diastolic blood pressure of more than 100 mm Hg. Twelve patients completed the trial. Both the drugs significantly reduced the blood pressure as compared to pretreatment values and the end-point, i.e. a supine diastolic blood pressure of 90 mm Hg or less, was achieved at the end of each treatment. However, the control of blood pressure appeared to be better sustained with labetalol. The side-effects, though minor in nature, were relatively more often observed with propranolol.