A twelve-week parallel study was conducted to compare the efficacy and safety of nicardipine plus propranolol with that of propranolol alone in 67 patients with mild to moderate essential hypertension. Efficacy data was analysed for 50 patients. The regimens used were 90 mg X day-1 of nicardipine and 120 mg X day-1 of propranolol. Both treatments significantly reduced supine and standing systolic and diastolic blood pressure from baseline values at all visits. At all visits, concomitant administration of nicardipine and propranolol produced a greater reduction in systolic and diastolic pressures than did propranolol alone, although the difference between treatments did not always reach statistical significance. Few adverse events were reported, and none was clinically important. We conclude that nicardipine taken concomitantly with propranolol is more effective than propranolol alone in treating patients with hypertension and that the combined regimen is well tolerated.