Note: these are for maintenance doses only at steady state. Do NOT use these guidelines for starting someone on warfarin.
|Less Than 1.3||Give them an extra dose and increase by 10% (always ask them if they “might” have missed a dose)|
|1.3 to 1.8||Increase weekly dose by 7 – 8% (always ask them if they “might” have missed a dose|
|1.8 – 2.0||Repeat the INR in one week, if still <2.0 than increase by 7%|
|2.0 t0 3.0||Smile|
|3.0 to 3.5||Check for patient errors in the dose first, then repeat the INR in 2 or 3 days. IF still elevated, decrease by 7% – 8%|
|3.5 to 4.5||Decrease by 7% – 8% (check for patient errors in the dose first)|
|Over 4.5||Hold the dose for one or two days and restart at a 10 – 20% lower weekly dose|
Often it is NOT necessary to give vitamin K. If you want to keep the patient anticoagulated, and you cannot stop yourself from giving vitamin K 🙂 … then give only 2.5 mg of phytonadione orally.
Do not give 10mg of vitamin K unless it is OK for the patient to NOT be anticoagulated for one or two weeks.
Obviously, you will usually give Vitamin K if the patient is bleeding.