Urapidil is a vasodilator acting on peripheral vessels by alpha-1 adrenoceptor blockade, and on central nervous system by alphaadrenoceptor blockade on the tractus solitarius nuclei and stimulation of serotoninergic receptors. Its hepatic metabolism and central action explain the absence of rebound effect when treatment is stopped. Urapidil is an arterial and venous vasodilator in systemic and pulmonary circulation. Therefore urapidil decreases systemic and pulmonary arterial pressures and left and right ventricular preload. These effects are accompanied by moderate effects on heart rate, and increased cardiac output in patients with heart failure. Some adverse effects observed with other vasodilators are absent (increased intracranial pressure and intrapulmonary shunt, negative inotropic effect, tachycardia). IV urapidil is used to treat systemic arterial hypertension perioperatively and hypertensive emergencies. Moreover urapidil has been administered to treat pulmonary artery hypertension in chronic pulmonary disease. Its haemodynamic effects seem proportional to the basal activity of alpha-adrenoceptors. Therefore, wide individual variations in active doses are observed from 12.5 to 50 mg as i.v. bolus in adults. Thereafter i.v. continuous administration or oral treatment may be necessary, depending on the cause of hypertension.