hepatic microsomal enzyme inhibiting substances

Last reviewed 01/2018

Drugs which inhibit hepatic enzymes may have the following effects:

  • they may increase the bioavailability of other drugs which are metabolised by those enzymes
  • they may decrease the bioavailability of drugs which require metabolism for their activation

Examples include:

  • alcohol consumed during 'binges'
  • antibiotics:
    • isoniazid
    • erythromycin
    • sulphonamides
    • metronidazole
    • chloramphenicol
    • ketoconazol
  • anticonvulsants, particularly valproate
  • cimetidine
  • allopurinol
  • chlorpromazine
  • imipramine
  • propranolol
  • metoprolol
  • interferon

Reference:

  • Adachi Y et al (1995). Potentiation of warfarin by interferon (letter). BMJ, 311, 292.