Acute antihypertensive effect of nifedipine by sublingual route in cases with clinically severe systolic hypertension. A study up to 4 h after administration.

In a multi-center study, nifedipine (Bay a 1040, Adalat) (10 mg capsule) was administered, in liquid form and via sublingual route, to 22 cases who were diagnosed to have clinically severe systolic hypertension, and the depressor effect of the treatment was studied over a period of 4 h. In patients of "emergent" admission (cerebral hemorrhage n = 8, cerebral thrombosis n = 4, subarachnoid hemorrhage n = 1, renal failure n = 6, essential hypertension n = 3), 3 bouts of blood pressure measurement at intervals of 10-15 min during the control period were carried out. In case of systolic blood pressure higher than 200 mmHg, at least one time, nifedipine at a dose of 10 mg was sublingually administered. Thereafter, blood pressure and pulse rate were recorded at intervals of 15 min up to the end of the first one hour, then at intervals of 30 min up to the end of 4 h. Results were as follows. In terms of the average values for all cases, blood pressure fell to near lowest levels by the end of about 30 min after the administration and it stayed at near lowest levels up to the end of 120-240 min. During this period of time, pulse rate remained substantially unchanged. In terms of the pattern of the blood pressure fall, all cases could be classified generally into two types, namely (a) the "dip" group (7 cases) in which blood pressure fell to the lowest level to form a "dip" and remained below the control level, although it showed a trend to return to control level for 4 h and (b) the "flat" group (15 cases) in which blood pressure declined gradually for about 1 h and, then, remained low or below the control level, although it showed a trend to return to control level throughout the rest of the observation period of 4 h.