What do the results mean?
If you were tested because you are taking warfarin, your results will probably be in the form of INR levels. INR levels are often used because they make it easier to compare results from different labs and different test methods. If you are not taking warfarin, your results may be in the form of INR levels or the number of seconds it takes for your blood sample to clot (prothrombin time).
If you are taking warfarin:
INR levels that are too low may mean you are at risk for dangerous blood clots.
INR levels that are too high may mean you are at risk for dangerous bleeding.
Your health care provider will probably change your dose of warfarin to reduce these risks.
If you are not taking warfarin and your INR or prothrombin time results were not normal, it may mean one of the following conditions:
A bleeding disorder, a condition in which the body can't clot blood properly, causing excessive bleeding
A clotting disorder, a condition in which the body forms excessive clots in arteries or veins
Liver disease
Vitamin K deficiency. Vitamin K plays an important role in blood clotting.
Learn more about laboratory tests, reference ranges, and understanding results.
