The pharmacokinetic parameters were estimated and the pharmacokinetic models of aprindine were evaluated in patients. Two pharmacokinetic models were used, comprising a linear elimination model and a non-linear elimination model, both one-compartment models in which first-order absorption is assumed. Twenty-two serum levels of patients in terms of TDM were measured and the pharmacokinetic parameters were estimated using the simple pool method. The pharmacokinetic parameters estimated using a linear model were ka= 0.244 (hr^-1), ke=0.020 (hr^-1) and Vd=1.778 (1/kg), while those using a non-linear model were ka=0.666 (hr-1), Km=2.022 (μg/ml), Vmax=0.106 (mg/hr/kg) and Vd=2.754 (1/kg).
The non-linear model was more suitable than the linear model for the AIC (linear model:-12.59, non-linear model:-19.61). The parameters estimated using the non-linear model were therefore more accurate and were found to have a smaller bias than those estimated using the linear model.