title: Metabolism of meperidine in several animal species.
abstract: Four new meperidine metabolites were identified by GC-MS in the urine of rats, guinea pigs, rabbits, cats, and dogs. In addition to known meperidine metabolites, 4-ethoxycarbonyl-4-phenyl-1,2,3,4-tetrapyridine (dehydronormeperidine; IV, the N-hydroxydehydro derivative of normeperidine (X), the dihydroxy derivative of meperidine (XII), and the dihydroxy derivative of normeperidine (XIII) were identified. The possible role of the N-hydroxy derivative of normeperidine (IX) in the pharmacological interaction of meperidine (I) with MAO inhibitors, seen selectively in the rabbit (and humans), is discussed. Following the administration of the p-hydroxy derivative of meperidine (VII), the major metabolite was conjugated VII. Trace amounts of the p-hydroxy derivative of normeperidine (VIII), the methoxy hydroxy derivative of meperidine (XI), XII, and XIII also were detected as metabolites of VII. The degree of N-demethylation of VII, both in vitro and in vivo, was small.
mesh_terms: D000818:Animals; D001711:Biotransformation; D002415:Cats; D002855:Chromatography, Thin Layer; D004285:Dogs; D008401:Gas Chromatography-Mass Spectrometry; D006168:Guinea Pigs; D006868:Hydrolysis; D008614:Meperidine / Q000031:analogs & derivatives / Q000378:metabolism* / Q000652:urine; D008996:Monoamine Oxidase Inhibitors / Q000494:pharmacology; D011817:Rabbits; D051381:Rats; D013045:Species Specificity
chemical_list: D008996:Monoamine Oxidase Inhibitors; C030549:4-hydroxymeperidine; D008614:Meperidine; C002752:normeperidine