Where can you find a chart showing standard INR levels?

Various websites, including Care Clinical Research, have charts showing standard, abnormal, normal and therapeutic INR levels. INR levels, which stand for international normalized ratio, are used to determine a person's prothrombin time, notes Mayo Clinic. This measurement is commonly used to monitor people taking warfarin or other oral anticoagulation therapy.

The higher a person's INR level is, the slower his blood clots. Generally, a person taking warfarin who has an INR between 2.0 and 3.0 generally has full anticoagulation, notes Mayo Clinic. If the INR level is above 4.0, there is a risk of serious bleeding. An INR below 2.0 means the patient is at an increased risk of thrombosis.