Re-evaluation of the metabolism and excretion of diethylpropion in non-sustained and sustained release formulations.
A direct gas chromatographic method for unstable amino ketones, using a neutral column and moderately alkaline conditions during extraction has been developed. Its application has given a new perspective to the relative importance of the metabolic routes in the complex metabolism of diethylpropion which after oral administration in man is rapid and extensive (only 3-4% of the drug remains unchanged). Mono-N-de-ethylation is the main pathway (about 35% of the dose). N-De-ethylation is more important than carbonyl-reduction, occurring mainly with the unchanged drug (about 20% of the dose). Norephedrine, thought previously to be one of the main metabolites, has been shown to be present only in negligible amounts. About 30% of the dose, which cannot be accounted for as the sum of the amines recovered in urine, is probably metabolized by deamination, followed by oxidation and conjugation to give hippuric acid.
D001711:Biotransformation; D002849:Chromatography, Gas; D003692:Delayed-Action Preparations; D004053:Diethylpropion / Q000008:administration & dosage / Q000378:metabolism* / Q000652:urine; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006207:Half-Life; D006801:Humans; D007700:Kinetics; D008297:Male; D013607:Tablets
D003692:Delayed-Action Preparations; D013607:Tablets; D004053:Diethylpropion