THE KINETIC PROFILES OF AMLODIPINE AND OF A SUSTAINED-RELEASE FORM OFDILTIAZEM

This study in normotensive subjects compared plasma concentrations of amlodipine (5 mg) and of a sustained release form of diltiazem (300 mg ) after single and multiple oral dosings of the two drugs. As a conseq uence of the galenic form of administered formulations, plasma concent ration of diltiazem versus time curves exhibited two peaks correspondi ng to fast and slow releases of diltiazem. Conversely, the curves of a mlodipine plasma concentration depicted only one peak. There was less variability in plasma concentrations and in pharmacokinetics with amlo dipine than with diltiazem after both single and multiple oral dosings of the two drugs. These results suggested that amlodipine displayed l ess variability in blood pressure response at steady-state. The rate o f decrease in plasma levels of diltiazem between 24 and 48 hours post- dose was higher than that of amlodipine. So, even after a missed dose, there is only a small decline in plasma concentrations of amlodipine and therefore it suggests a small repercussion on the blood pressure a ttenuation.