Induction of polymorphic 4'-hydroxylation of S-mephenytoin by rifampicin.

@article{Zhou1990InductionOP,
  title={Induction of polymorphic 4'-hydroxylation of S-mephenytoin by rifampicin.},
  author={H. Zhou and L. Anthony and A. Wood and G. Wilkinson},
  journal={British journal of clinical pharmacology},
  year={1990},
  volume={30 3},
  pages={
          471-5
        }
}
Studies were performed in 13 healthy subjects to determine whether treatment with rifampicin results in induction of the metabolism of mephenytoin. Daily dosing with 600 mg rifampicin for 22 days caused a three to eightfold increase in the 0-8 h urinary R/S ratio of mephenytoin following oral administration (100 mg) of racemic drug to extensive metabolizers of the anticonvulsant. This was accompanied by a 40 to 180% increase in the 0-8 h urinary excretion of the 4'-hydroxy metabolite. Four… Expand
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