Effect of chlormethiazole on hepatic monooxygenases activity in vivo

Eur J Clin Pharmacol. 1993;44(2):203-4. doi: 10.1007/BF00315482.


Chlormethiazole is a strong inhibitor of cytochrome P-450-dependent monooxygenases in isolated human liver microsomes. To assess its effect in vivo, we measured the pharmacokinetic parameters of antipyrine (1.2 g orally) and tolbutamide (0.5 g i.v.) before and after administration of chlormethiazole 314 mg b.d. for 2 days to 8 healthy volunteers. The elimination of neither substance was affected, indicating that chlormethiazole did not inhibit in vivo the cytochrome P-450 isozymes responsible for the elimination of antipyrine and tolbutamide.

MeSH terms

  • Antipyrine / pharmacokinetics
  • Chlormethiazole / pharmacology*
  • Half-Life
  • Humans
  • Liver / drug effects
  • Liver / enzymology*
  • Male
  • Mixed Function Oxygenases / metabolism*
  • Tolbutamide / pharmacokinetics


  • Chlormethiazole
  • Tolbutamide
  • Mixed Function Oxygenases
  • Antipyrine