A controlled comparison of the antihypertensive effects of labetalol and alpha-methyldopa.

An open crossover study was carried out in 10 Arab patients with mild to moderate hypertension to compare the effectiveness and tolerability of labetalol with alpha-methyldopa. Patients were started on either 100 mg labetalol or 250 mg alpha-methyldopa 3-times daily and, if necessary, the dosage adjusted by standard increments every 2 weeks over a period of a month until satisfactory control was achieved. This dosage was then maintained for a further 6 weeks before the patients were crossed over to the alternative treatment, similarly adjusted, after a wash-out period of 2 weeks on placebo. The results showed that both treatments produced effective blood pressure control and there was no significant difference in the maximum reduction achieved. The effect of the two drugs on heart rate was also similar. Both treatments were generally well-tolerated and side-effects were mild and similar with either drug.