Clinical Pharmacokinetics

, Volume 29, Supplement 1, pp 20–25 | Cite as

Drug Interactions and the Cytochrome P450 System

The Role of Cytochrome P450 1A2
  • Kim Brøsen


Cytochrome P450 1A2 (CYP1A2) accounts for about 10 to 15% of the total CYP content of human liver and is the major enzyme involved in the metabolism of imipramine, propranolol, clozapine, theophylline, and caffeine. It is also involved in the conversion of heterocyclic amines to their proximal carcinogenic and mutagenic forms, as well as in the metabolism of endogenous substances, including 17β-estradiol and uroporphyrinogen III. Fluvoxamine is a potent inhibitor of CYP1A2, and there is potential for interaction with drugs that are metabolised by this isoenzyme. This property of fluvoxamine may be usefully applied to identifying agents that are substrates of CYP1A2, and it has a possible therapeutic application in the prevention of CYP1A2-mediated toxic metabolite formation.


Theophylline Clozapine Imipramine Fluvoxamine Phenacetin 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Adis International Limited 1995

Authors and Affiliations

  • Kim Brøsen
    • 1
  1. 1.Department of Clinical Pharmacology, Institute of Medical BiologyOdense UniversityOdenseDenmark

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