Average daily dosing

  • Most patients: start therapy at 5mg daily and adjust according to INR results
  • Sensitive patients: start therapy at 1 - 2.5mg daily and adjust according to INR results

Factors that increase sensitivity to warfarin:

Age > 75 years Clinical congestive heart failure
Asian race Clinical hyperthyroidism
Elevated baseline INR End stage renal failure
Fever Malignancy
Diarrhea Following heart valve replacement
Known CYP2C9 variant Hepatic disease
Hypoalbuminemia Decreased overall oral intake
Malnutrition CYP-inhibition drug interactions