Warfarin sensitivity: be aware of genetic influence.
BACKGROUND
avoidance of over anticoagulation in response to warfarin therapy would reduce risk of associated bleeding.


METHODS
two elderly patients with venous thromboembolism exhibited extreme anticoagulant response to warfarin. Both were noted to have variant CYP2C9 alleles, which reduce the metabolic capacity of cytochrome P450 2C9.


CONCLUSIONS
adverse outcomes with warfarin therapy could be explained and possibly avoided by identifying patients with variant alleles for CYP2C9 before initiation of therapy.
Khan
Tayyaba
T
Department of Pharmacological Sciences, University of Newcastle upon Tyne, Newcastle Upon Tyne NE1 4LP, UK.
Kamali
Farhad
F
Daly
Ann
A
King
Barry
B
Wynne
Hilary A
HA
D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D000925:Anticoagulants / Q000009:adverse effects*; D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics; D065729:Cytochrome P-450 CYP2C9; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D013924:Thrombophlebitis / Q000188:drug therapy; D014859:Warfarin / Q000009:adverse effects*
D000925:Anticoagulants; D014859:Warfarin; C450260:CYP2C9 protein, human; D065729:Cytochrome P-450 CYP2C9; D001189:Aryl Hydrocarbon Hydroxylases