ISOLATION AND IDENTIFICATION OF URINARY METABOLITES OF OXYCODONE IN RABBITS

Abstract

In the rabbit the metabolism of the analgesic and antitussive oxycodone was studied. It proceeded through 5 metabolic pathways: O-demethylation, N-demethylation, N-oxidation, 6-keto reduction and glucuronidation. Six urinary metabolites and unchanged oxycodone were isolated and identified in the unconjugated form: 14-hydroxydihydromorphinone, 14-hydroxydihydrocodeine, 14-hydroxydihydrocodeinone N-oxide (oxycodone N-oxide), 14-hydroxydihydroisocodeine, 14-hydroxydihydrocodeine N-oxide and noroxycodone. Identification was made by various chromatographic and spectral comparisons with authentic samples. Oxycodone, 14-hydroxydihydromorphinone, 14-hydroxydihydrocodeine, 14-hydroxydihydroisocodeine and noroxycodone were identified as aglycons of conjugated metabolites.