[Antihypertensive effect and tolerance to urapidil. Comparison with nifedipine in a multicenter double-blind study]

In a multi-center, double-blind parallel-group study involving patients with essential hypertension (grade I/II), the antihypertensive effect and toleration of the postsynaptic alpha-1 receptor blocker, urapidil, was compared with that of the calcium antagonist, nifedipine. After a one-week wash-out, and one week period on placebo, the patients received either urapidil 60 mg in the morning and evening (n = 81), or nifedipine retard 20 mg mornings and evenings (n = 87), over a period of 12 weeks. The results show that urapidil and nifedipine administered alone, produce an effective lowering of blood pressure. The reduction in systolic blood pressure-approximately 12 hours after the last administration-was, on average, 10 mmHg for urapidil, and 14 mmHg for nifedipine. The reduction in systolic blood pressure was more marked under nifedipine (19 mmHg) than under urapidil (10 mmHg). The difference in heart rate at the end of the treatment phase did not differ significantly from the pre-treatment figure with either drug. The 12-week treatment with urapidil and nifedipine had no effect on lipid metabolism. Fourteen patients receiving urapidil, and 24 patients on nifedipine complained of undesirable side effects (in particular headaches and giddiness). Flushing occurred only in the nifedipine group. 8 patients on urapidil and 3 on nifedipine discontinued due to side effects.