[Review of a technic for the estimation of area under the concentration curve in pharmacokinetic analysis]

The determination of the area under concentration-time curve (AUC) is the most important parameter of a non-compartmental pharmacokinetic analysis. The calculation of AUC is usually performed by the trapezoidal rule. The aim of this work is to examine the reliability of this method still considered as a reference. The trapezoidal rule was compared to a selection of calculation methods often owning to other fields of research i.e., rectangular rule, Simpson and Tchebychev rules and log trapezoidal rule. The specific interest and limits of each method were discussed according to the kind and the type of pharmacokinetic profiles i.e., logarithmic or nonlogarithmic and the number of concentration-time couples. We obtained the following results: 1) The rectangular rule is the most simple and less effective method. 2) The trapezoidal rule remains an interesting method particularly when the profile is monologarithmic or nonlogarithmic. The efficacy of this method increases with the number of points of the pharmacokinetic profile. 3) The Simpson and the Tchebychev rules give very good results particularly when the number of points is higher than 7 and 6 respectively. 4) The log trapezoidal rule is an excellent method for the treatment of a logarithmic profile. 5) Both Tchebychev and log trapezoidal rules give accurate results when compared to the true AUC values. Further, it must be pointed out that this determination is depending on an arbitrary choice of points. Finally, the trapezoidal rule is not always the best method to determine AUC. If the analyst has only a pocket-calculator, he will obtain best results with the Simpson method than with the trapezoidal rule.(ABSTRACT TRUNCATED AT 250 WORDS)