Pharmacokinetic study of cephradine in Pakistani healthy male volunteers.

To observe and discuss the difference in the pharmacokinetics of cephradine in Pakistani population with the reported data of other ethnic origins. A Single group pharmacokinetic study was conducted having six healthy male volunteers of 20-24 years of age. Blood samples were collected at appropriate times up to 7 hours. Plasma concentrations of cephradine was determined by HPLC technique and pharmacokinetic parameters were determined by both compartmental and noncompartmental methods using Kinetica ver 4.4.1 and Winnonlin ver 5.01. Peak plasma concentration was 11.49+/-1.73 microg/ ml achieved at 0.76+/-0.12 hr, after the administration of 250 mg cephradine to fasting volunteers. Area under the serum concentration-time curve was found to be 16.4+/-1.71 g.hr/ ml. Absorption, distribution, disposition and elimination half lives were calculated as 0.183 +/- 0.038 hr, 0.248 +/- 0.143 hr, 2.126 +/- 0.341 hr and 0.441+/-0.193 hr respectively where as the volume of central compartment and total body clearance were found to be 9.65+/-3.78 L and 15.4+/-1.89 L/hr. The plasma concentration time curves showed the absorption rate constant was 3.968 +/- 0.05 hr(-1), disposition rate constant was 0.333+/-0.05 hr(-1), distribution rate constant was 3.64+/-2.18 hr(-1) and elimination rate constant was 1.738+/-0.468 hr(-1). The value of micro-constants i.e. K(12) (central to peripheral compartment) and K(21) (peripheral to central compartment) were found to be 1.529+/- 1.499 hr(-1) and 0.704 +/- 0.44 hr(-1) respectively, where as MRT and AUMC were calculated as 2.04+/-0.09 hr and 35.92+/-1.86 hr(2) microg/ ml. The findings showed that the results of Pakistani subjects are slightly different when compared with the reported data of other ethnic origin.