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Clinical effect of CYP2C9*5/*6 genotype on a patient's warfarin dose requirement

Alison Lh Quinn1, Ina Liko1, James C Lee1

  • 1Department of Pharmacy Practice, University of Illinois at Chicago College of Pharmacy, Chicago, IL 60612, USA.

Pharmacogenomics
|July 8, 2017
PubMed

We describe a 38-year-old African-American female treated with warfarin for acute bilateral pulmonary emboli who is a carrier of two rare CYP2C9 variant alleles, *5 and *6, along with VKORC1 -1639GG and CYP4F2 433Val/Val genotypes. Warfarin was dosed according to the hospital's Personalized Medicine Program recommendations of 5-6 mg/day for the first 6 days, and reduced to 2.5 mg/day starting on day 8 and continued for the following 3 weeks. This case sheds further light on the cumulative clinical impact of the CYP2C9 variant alleles, *5 and *6, on warfarin dose requirements and practical considerations for warfarin genotyping in a racially and ethnically diverse population.

Keywords:
CYP2C9*5CYP2C9*6anticoagulationpersonalized medicinepharmacogeneticswarfarin

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