Choice of optimum pharmacokinetic model of orally administered paracetamol

The present work studies the characterization of the pharmacokinetic profile of paracetamol following oral administration of DUOROL® tablets containing 500 mg of the active compound. Analysis is made of the influence of statistical weighting on the selection of the pharmacokinetic model chosen. In the model proposed, the uptake of the drug into the systemic circulation is described by two first-order sequential kinetic processes. The values of the first order rate constants that define the absorption process have values of 4.79 and 9.73h−1. Validation of the absorption model proposed was performed by applying the Wagner-Nelson method, according to which values of 4.63 and 10.95 h−1 were obtained for each of the constants defining the uptake of the drug into the systemic circulation.