[Study of the influence of the time of administration on the antihypertensive effect and nitrendipine tolerance in mild to moderate essential hypertensive patients. Value of ambulatory recording of blood pressure on 24 hours]

Forty-one patients with mild to moderate hypertension were included in a multicentre trial. The objective was to assess the influence of the time at which nitrendipine (Nidrel 20 mg) is taken on its efficacy and tolerance. The drug was administered once daily either in the morning or in the evening during 2 consecutive periods of 28 days. Efficacy was assessed on an ambulatory recording of blood pressure over 24 hours. Globally, nitrendipine results in a statistically significant drop in blood pressure which is not influenced by the time of administration. Treatment response varies greatly according to the initial value of ambulatory diastolic blood pressure. There is a clear antihypertensive effect if ADBP is greater than or equal to 90 mmHg and no hypotensive effect if ADBP is less than 90 mmHg. The incidence of adverse effects did not vary according to the time the drug was taken. Biological tolerance was excellent. Nitrendipine, administered once daily alone appears to be an efficient antihypertensive agent, well tolerated both clinically and biologically. Its efficacy is maintained over a 24-hour period regardless of the time at which the drug is taken.