The Simulation of the Relevance of Absorption Rate Constant and Elimination Rate Constant to the Plasma Drug Concentration

To investigate how the concentration characteristics vary with the changing parameters absorption rate constant (K
_a
) and elimination rate constant (K
₁₀
) this study simulates a two-compartment model with first-order absorption for oral administration. Based on the MATLAB software the simulations illustrated the results of the variation of the concentration characteristics in two- and three-dimensional diagrams. It was showed that the peak plasma concentration (C
_max
) increased and the time required to reach this peak (T
_max
) decreased with the increasing K
_a
. However, with increasing K
₁₀
both the C
_max
and the T
_max
decreased. Results demonstrate that the profiles are meaningful for the selection of the rational range of K
_a
and K
₁₀
, and the identification of the flip-flop kinetic.