[Long-term blood pressure measurement for evaluating the first dose response of captopril and ramipril in patients with a stimulated renin system].

First-dose-response of captopril 1 x 25 mg (no prodrug) and ramipril 1 x 2.5 mg (prodrug) were compared in two groups of 17 patients with moderate or severe hypertension and stimulated renin-angiotensin system (because of continuous diuretic therapy) by means of 24-h blood-pressure measurement at the 1st and 7th day of therapy. In the ramipril-group the antihypertensive effect started after 2 h, had its maximum (mean: -13/-8 mmHg) after 4 h and remained unchanged for 8 h. The antihypertensive effect was significant for 24 h. There was a slightly but not significant improved blood-pressure reduction at the 7th day compared to the 1st. The captopril-group showed a fast and marked decrease of blood pressure within the first hour, and reached its maximum (mean: -18/-10 mmHg) after 2 h. After 7 h there was no antihypertensive effect detectable. At the 7th day blood-pressure reduction was less pronounced compared to the 1st day. The results show that initial decrease of blood pressure in risk-patients is less severe with prodrug-ACE-inhibitors with slow onset of action so that counterregulation can be activated and prevent severe, fast, ACE-inhibitor-induced hypotension. 24-h-blood-pressure measurement is a sufficient method to evaluate first-dose-response of ACE-inhibitors.