title: Warfarin therapy--why one dose does not fit all!
abstract: We report an Indian adult female patient with Deep Vein Thrombosis (DVT), in whom it was difficult to achieve and maintain target INR on warfarin (oral anticoagulant) by conventional doses. Pharmacogenomics study for warfarin revealed that she had Homozygous mutant for CYP2C9 *3(CYP2C9 *3/*3) and Heterozygous mutant for VKORC 1(1639G >A) {genetic polymorphism double defect}. This conferred a greater sensitivity to her warfarin therapy in an otherwise conventional dose regime used in most patients, making her management challenging. This sensitivity (or resistance in other cases) can be assessed by this evidence based test and warfarin dosing could be individualised to avoid toxicity.
authors.forename: Vrinda
authors.initials: V
authors.lastname: Kulkarni
authors.forename: Abhay
authors.initials: A
authors.lastname: Bhave
authors.forename: Renuka Kulkarni
authors.initials: RK
authors.lastname: Munshi
authors.forename: Supriya
authors.initials: S
authors.lastname: Bhalerao
authors.forename: Dhiraj
authors.initials: D
authors.lastname: Bhattad
authors.forename: Santosh
authors.initials: S
authors.lastname: Khude
authors.forename: Dnyneshwar
authors.initials: D
authors.lastname: Upase
mesh_terms: D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics; D065729:Cytochrome P-450 CYP2C9; D005260:Female; D006801:Humans; D019934:International Normalized Ratio; D008875:Middle Aged; D009154:Mutation; D020246:Venous Thrombosis / Q000097:blood / Q000188:drug therapy*; D064417:Vitamin K Epoxide Reductases / Q000235:genetics; D014859:Warfarin / Q000008:administration & dosage*
chemical_list: D014859:Warfarin; C450260:CYP2C9 protein, human; D065729:Cytochrome P-450 CYP2C9; D001189:Aryl Hydrocarbon Hydroxylases; C578523:VKORC1 protein, human; D064417:Vitamin K Epoxide Reductases