The metabolite pattern of d-propoxyphene in man. The use of heavy isotopes in drug disposition studies

Through the combined use of deuterium labeling and GC-MS analysis, eight urinary metabolites of d-propoxyphene have been identified in man following a single oral dose of 130 mg of d-propoxyphene. The metabolites present were: norpropoxyphene, dinorpropoxyphene, cyclic dinorpropoxyphene, propoxyphene carbinol, norpropoxyphene carbinol, dinorpropoxyphene carbinol, p-hydroxypropoxyphene and p-hydroxynorpropoxyphene. The latter two metabolites occur as conjugates. The persistent metabolite, previously identified as norpropoxyphene, was found to be a mixture of norpropoxyphene and dinorpropoxyphene.