Ambulatory blood pressure profiles in essential hypertensives after treatment with a new once daily nifedipine formulation

The antihypertensive efficacy of a new controlled release preparation of ni fedipine developed for once daily administration was investigated in compar ison with a standard therapy with sustained-release nifedipine given twice daily in a randomised, open crossover trial. Twenty-two patients with mild to moderate essential hypertension were enrolled. Ambulatory blood pressure monitoring (ABPM) was performed after a wash-out period and after a 3 week s treatment with 40 mg controlled-release nifedipine once daily and 20 mg s ustained-release nifedipine twice daily, respectively. ABPM data were evalu ated by conventional linear analysis and by rhythm analysis. Both once dail y and twice daily administration of nifedipine significantly reduced systol ic blood pressure during the daytime and during the night when compared wit h baseline. The 24-h diastolic blood pressure was significantly decreased b y both treatments, but only the once daily regimen significantly lowered bo th diastolic daytime and night-time means. Comparing systolic and diastolic blood pressures after both treatments, however, no significant differences were obtained. Both nifedipine treatments did neither greatly modify the c ircadian blood pressure pattern nor reflexly increase heart rate. In conclu sion, once daily application of the controlled-release formulation of nifed ipine resulted in a consistent and significant blood pressure reduction. On ce daily and twice daily medications of nifedipine were about equally effec tive in lowering the elevated blood pressures.