Abstract
A study on the frequency distribution of various pharmacokinetic parameters was conducted using pharmacokinetic data based on human blood samples obtained after administration of three cephalosporin derivatives. The results indicated that pharmacokinetic parameters ka, ke, V, α, β, k12, k21, V1, Vd and Cl followed lognormal distribution curves rather than normal distribution curves. Thus, in the case of a one-compartment open model, it was demonstrated that mean plasma concentration-time curves could be prepared more precisely by use of the geometrical mean values of V, ke and ka. In the case of a two-compartment open model, the use of the geometrical mean values of V1, α, β and ke rather than those of V1, k12, k21 and ke was considered to be preferable in view of the reliability of the rate constants α, β, k12 and k21.
