Relative Bioavailability and Bioequivalence of Amlodipine Besylate Tablets in Healthy Volunteers

Objective To evaluate the pharmacokinetics and bioavailability of two formulations of amlodipine tablets in 20 healthy male volunteers. Methods A total of 20 healthy male volunteers were orally given a single dose of 10 mg of two different formulations of amlodipine in an open randomized cross-over test. The amlodipine concentration in plasma was determined by ultraperformance liquid chromatography-tandem mass spectrometry. Results The main pharmacokinetic parameters of tested and reference tablets were as follows:Tmax of amlodipine were 6.32±0.85 h and 5.95± 1.23 h,Cmax were 6.231±1.734 ng· mL-1and 6.138±1.352 ng· mL-1,T1/2 were 39.89±9.43 h and 40.02±7.49 h and AUC0-144 were 273.473±97.167 ng· h· mL-1and 278.314±80.340 ng· h· mL-1,AUC0-∞ were303.480±106.054ng· h· mL-1and 306.412±91.351 ng· h· mL-1,respectively.Therelative bioavailability was 99.7%±20.2%. Conclusion The results demonstrate that the tested and reference tablets are bioequivalent.