Effect of food ingestion on nifedipine absorption and haemodynamic response

The absorption of nifedipine (10 mg) and haemodynamic response were studied in 10 patients with myocardial infarction before (Phase A) and after (Phase B) a standardized breakfast. In Phase A, the peak nifedipine concentration (Cmax) and maximum haemodynamic changes were found 1 h after drug administration. In Phase B, the Cmax was lower than that in phase A (43 +/- 6 vs 136 +/- 23 ng/ml, p less than 0.001), and both Cmax and maximum haemodynamic changes were delayed to the fourth hour after administration. Nifedipine plasma concentration correlated significantly with the percent changes in systolic and diastolic blood pressure and heart rate. This study suggests that not only dose but also the time intervals between nifedipine administration and food intake are important in determining the haemodynamic effects.