Urinary metabolism of dextromethorphan in man.

: After an oral dose of 50 mg of (+)-3-methoxy-N-methylmorphinan (dextromethorphan) to volunteers, urinary metabolism was studied by gas chromatography/mass spectrometry. A total of 15 previously unknown metabolites and derivatives of dextromethorphan could be identified by mass spectrometric techniques. The main metabolic pathways were: O,N-demethylation, O,N-acetylation, hydroxylation of the phenyl ring and the saturated ring system with subsequent further oxidation.