Anticoagulation

Question 1

What are the different colour tablets and doses that come with warfarin?

Answer 1

White= 0.5mg (500 microgram) 
Brown= 1mg 
Blue= 3mg 
Pink= 5mg

Question 2

What is the implication of a low INR and a high INR?

Answer 2

Low INR indicates potential clotting risk, whilst high INR indicates potential bleeding risk.

Question 3

Warfarin dosing?

Answer 3

High warfarin dose = high INR

Lowering warfarin dose = Lower INR

Question 4

What should be done with warfarin when a patient’s INR is out of range?

Answer 4

• Greater than 8 with minor bleeding — stop warfarin and give phytomenadione by slow intravenous injection. If no bleeding was present give phytomenadione by mouth using the intravenous preparation orally (off-label use).
  The dose of phytomenadione may be repeated after 24 hours if the INR is still too high.
  Restart warfarin when the INR is less than 5.
• Between 5–8 with minor bleeding — stop warfarin and give phytomenadione by slow intravenous injection.
  Restart warfarin when the INR is less than 5.
• Between 5–8 with no bleeding — withhold 1 or 2 doses of warfarin and reduce subsequent maintenance dose.