Systemic haemodynamic and humoral changes during urapidil treatment in hypertensive patients

Urapidil, a new antihypertensive agent exerting a peripheral alpha 1-postsynaptic blocking action and an additional action at the central level, has some characteristics which may correct the underlying pathophysiological abnormalities found in the great majority of hypertensive patients. When administered acutely and chronically, urapidil significantly lowers blood pressure in hypertensive patients by reducing total peripheral resistance, while cardiac output is unchanged or only slightly elevated. The blood pressure reduction can cause a decrease in cardiac mass in patients with left ventricular hypertrophy. Urapidil has been successfully administered also in patients with congestive heart failure and in hypertensive crises during or following surgical procedures; in all these conditions urapidil lowers total peripheral resistance, but blood pressure is lowered only in patients with hypertensive crises and no clinically relevant reduction in blood pressure is found in patients with congestive heart failure. The acute administration of urapidil has shown a trend towards a rise in plasma renin activity, in plasma aldosterone and in plasma catecholamines; on the whole, however, the activation of these systems has been mild.