Bioequivalence of diltiazem in control and sustained release capsules in healthy volunteers

Objective To evaluate the bioequivalence of diltiazem control capsule and slow release capsule in Chinese healthy volunteers Methods A single oral dose (180 mg) of two diltiazem capsule was given to 18 healthy in a randomized cross-over study. The concentration of diltiazemin plasma were determined by HPLC-UV method developed in our laboratory.Results The main pharmacokinetic parameters of diltiazem in two formulations, control and sustained release capsules, were as follow:single dose :tmax were(14.1±3.9)h and(8.4±4.1)h,Cmax were(73±37) and(94±44)ng·mL-1, AUC0-36 were(1348±590)and (1571±679)ng·h·mL-1,t1/2 were(7.9±2.9)and(8.0±3.5) h ;multi-dose: tmax were(8.1±5.0)h and和(4.8±2.7)h,Cmax were(145±41)and(170±58)ng·mL-1, AUCss were(2232±642)and(2419±658)ng·h·mL-1,DF were (103±32)% and(123±32)%.Conclusion The two praperations are bioequivalence after multidose.