Cross inhibition of drug metabolism by drug metabolites. Increase of zoxazolamine paralysis time by the major metabolite of diphenylhydantoin

W. C. Lubawy, H. B. Kostenbauder, S. A. Stavchansky

Research output: Contribution to journalArticle

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The ability of the major metabolite of diphenylhydantoin, 5 (p hydroxyphenyl) 5 phenylhydantoin (HPPH), to affect the duration of action and metabolic rate of type II compounds was examined. Administration of HPPH prolonged the paralysis produced by zoxazolamine in intact rats. Additionally HPPH inhibited the metabolism of zoxazolamine and aniline in rat hepatic 9000 g supernatant. Cross inhibition of drug metabolism by drug metabolites presents a serious potential for drug to drug interactions.

Original languageEnglish
Pages (from-to)75-82
Number of pages8
Issue number1
Publication statusPublished - 1 Dec 1974


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