Placebo-controlled, double-blind clinical trial of alprenolol in African hypertensive patients.

A placebo-controlled, double-blind clinical trial of alprenolol was carried out in 20 hypertensive Africans. The active drug and placebo were each administered for 8 weeks using a crossover design. Alprenolol was given in the form of a slow-release tablet preparation at a dosage of 200 mg twice daily. Four patients were withdrawn from the study either because of side-effects (2 patients) or non-compliance (2 patients). The mean reduction in blood pressure obtained in the 16 patients who completed the trial was less than that usually reported in Caucasians.