Anticoagulation Service For Health Professionals

Warfarin Dose Adjustment

Target INR 2.5 (Range 2.0 - 3.0)

Patient's INR < 1.5 1.5 - 1.9 2.0 - 3.0 3.1 - 3.9 4.0 - 4.9 > 5.0
Dose Change Increase 10 - 20%.
Consider extra dose		 Increase 5 - 10%* No Change Decrease 5 - 10%** Hold 0 - 2 day and
decrease 10% 		Refer to
appropriate algorithm
Next INR 4 - 8 days 7 - 14 days See follow - up
algorithm 		7 - 14 days 4 -8 days  

Follow - up Algorithm
# Consecutive In - range INRs Repeat INR in
1 5 - 10 days
2 2 Weeks
3 3 weeks
4 4 weeks
Note: If INR 2.0 - 2.1 or 2.9 - 3.0, consider repeat INR in 2 - 3 weeks regardless of # of consecutive in - range INRs.
For pts w/ many consecutive therapeutic INRs, the F/U algorithm may be accelerated for a single out - of - range INR.

* If INR 1.8 - 1.9, consider no change w/ repeat INR in 7 - 14 days.

** If INR 3.1 - 3.2, consider no change w/ repeat INR in 7 - 14 days.

Remember:
1. Always consider trend in INRs when making warfarin management decisions.
2. Consider repeating INR same day or next day if observed value markedly different than expected value. (Potential for lab errors exist)

Date of last revision: 10/06

Target INR 3.0 (Range 2.5 - 3.5)

Patient's INR < 1.5 1.5 - 2.4 2.5 - 3.5 3.6 - 4.4 4.5 - 4.9 > 5.0
Dose Change Increase 10 - 20%. Consider extra dose Increase 5 - 10%* No Change Decrease 5 - 10%** Consider holding
1 dose 		Hold 0-1 day and decrease 10% Refer to appropriate algorithm
Next INR 4 - 8 days 7 - 14 days See follow - up algorithm 7 - 14 days 4 - 7 days  

Follow - up Algorithm
# Consecutive In - range INRs Repeat INR in
1 5 - 10 days
2 2 Weeks
3 3 weeks
4 4 weeks
Note: If INR 2.5 - 2.6 or 3.4 - 3.5, consider repeat INR in 2-3 weeks regardless of # of consecutive in - range INRs.
For pts w/ many consecutive therapeutic INRs, the F/U algorithm may be accelerated for a single out - of - range INR.

* If INR 2.3 - 2.4, consider no change w/ repeat INR in
7 - 14 days.

** If INR 3.6 - 3.7, consider no change w/ repeat INR in 7 - 14 days.

Remember:
1. Always consider trend in INRs when making warfarin management decisions.
2. Consider repeating INR same day or next day if observed value markedly different than expected value. (Potential for lab errors exist)

Reviewed 10/06