Kinetics of Methaemoglobin Production (2). Kinetics of the Cyanide Antidote p-Aminopropiophenone During Oral Administration

Abstract

The kinetics of methaemoglobin production by orally administered p-aminopropiophenone (PAPP) was studied by using a kinetic model previously developed to describe methaemoglobinaemia consequent on intravenous injection of PAPP. Both ISIS, a simulation package, and NONLIN, a non-linear least-squares regression analysis program, were used to analyse the data. Some modification of the model was necessary to describe oral profiles and 40-50% of the administered PAPP appeared to be being metabolized at first pass to a non-active metabolite.