Antihypertensive effects of urapidil and clonidine: a double-blind cross-over study.

The antihypertensive effects of urapidil and clonidine have been studied in a double-blind cross-over trial in 11 hypertensive outpatients with mild to moderate hypertension, at rest and during isometric exercise. Urapidil 30 mg b.i.d. significantly decreased the standing diastolic blood pressure (p less than 0.05) and the systolic blood pressure at the end of isometric exercise (p less than 0.05). Clonidine 0.075-0.15 mg b.i.d. was more effective in decreasing both systolic and diastolic blood pressure in the supine and standing positions as well as during isometric work (p less than 0.05-0.001). Urapidil caused fewer side-effects than clonidine. Overall, in the doses used urapidil had a weaker antihypertensive effect and caused fewer side-effects than clonidine.