What Is the INR Value in Blood?

What Is the INR Value in Blood?

INR, or international normalized ratio, is another way to report prothrombin time, states MedlinePlus. Prothrombin time measures how long it takes for blood plasma to clot.

A normal INR level ranges from 0.8 to 1.1 in people who are not taking blood thinners, reports MedlinePlus. Someone who takes warfarin, a blood-thinning medication, may need to maintain a higher INR of 2.0 to 3.0. An INR of greater than 1.1 in a patient who is not taking blood thinners indicates undesirably slow blood clotting; this can be caused by issues such as liver disease, vitamin K deficiency or problems with the clotting mechanism of the blood.