A Case of Intolerance to Warfarin Dosing in an Intermediate Metabolizer of CYP2C9.
10.3349/ymj.2005.46.6.843
- Author:
Soo Youn LEE
1
;
June Soo KIM
;
Jong Won KIM
Author Information
1. Department of Laboratory Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
- Publication Type:Case Report ; Research Support, Non-U.S. Gov't
- Keywords:
Warfarin;
cytochrome P-450 CYP2C9;
polymorphism;
prothrombin time;
pharmacogenetics
- MeSH:
Warfarin/administration & dosage/*adverse effects/metabolism;
Prothrombin Time;
Polymorphism, Genetic;
Humans;
Female;
Dose-Response Relationship, Drug;
DNA Mutational Analysis;
Aryl Hydrocarbon Hydroxylases/*genetics/metabolism;
Anticoagulants/administration & dosage/*adverse effects/metabolism;
Adult
- From:Yonsei Medical Journal
2005;46(6):843-846
- CountryRepublic of Korea
- Language:English
-
Abstract:
We report a case of intolerance to warfarin dosing due to impaired drug metabolism in a patient heterozygous for the CYP2C9*3 allele. A 30-year-old woman with an artificial cardiac pacemaker was taking warfarin to prevent thromboembolism. This patient had an extremely elevated international normalized ratio (INR) of prothrombin time (PT) following standard doses of warfarin and experienced difficulties during the induction of anticoagulation. Genotyping for CYP2C9 revealed that this patient was an intermediate metabolizer with genotype CYP2C9*1/*3. This case suggests the clinical usefulness of pharmacogenetic testing for individualized dosage adjustments of warfarin.
