Clinical Significance of the Cytochrome P450 2C19 Genetic Polymorphism

@article{Desta2002ClinicalSO,
  title={Clinical Significance of the Cytochrome P450 2C19 Genetic Polymorphism},
  author={Zeruesenay Desta and Xiaojiong Zhao and Jae-Gook Shin and David A. Flockhart},
  journal={Clinical Pharmacokinetics},
  year={2002},
  volume={41},
  pages={913-958}
}
Cytochrome P450 2C19 (CYP2C19) is the main (or partial) cause for large differences in the pharmacokinetics of a number of clinically important drugs. On the basis of their ability to metabolise (S)-mephenytoin or other CYP2C19 substrates, individuals can be classified as extensive metabolisers (EMs) or poor metabolisers (PMs). Eight variant alleles (CYP2C19*2 to CYP2C19*8) that pre-diet PMs have been identified. The distribution of EM and PM genotypes and phenotypes shows wide interethnic… 
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TLDR
The traditional and validated therapeutic drug monitoring approach, representing a direct ‘phenotype’ assessment, still remains the method of choice when an individualised dosing regimen is anticipated, but pharmacogenetics and pharmacogenomics can offer some novel contributions when attempts are made to maximise drug efficacy and enhance drug safety.
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