What is the PT INR test?

A prothrombin time (PT) is a test used to help detect and diagnose a bleeding disorder or excessive clotting disorder; the international normalized ratio (INR) is calculated from a PT result and is used to monitor how well the blood-thinning medication (anticoagulant) warfarin (Coumadin®) is working to prevent blood …

How do you test for PT INR?

If you are taking warfarin, your provider may recommend you test your blood regularly using an at-home PT/INR test kit. During this test, you or your provider will: Use a small needle to puncture your fingertip. Collect a drop of blood and place it onto a test strip or other special instrument.

What is normal PT INR?

In healthy people an INR of 1.1 or below is considered normal. An INR range of 2.0 to 3.0 is generally an effective therapeutic range for people taking warfarin for disorders such as atrial fibrillation or a blood clot in the leg or lung.

When would a PT INR test be used?

A PT/INR test is most often used to: See how well Warfarin is working. Warfarin is a blood-thinning medicine that’s used to treat and prevent dangerous blood clots. (Warfarin This medication is used to treat blood clots and/or to prevent new clots from forming in your body. is a common brand name for warfarin.)

What causes elevated PT INR?

Common causes of a prolonged PT include vitamin K deficiency, hormone drugs including hormone replacements and oral contraceptives, disseminated intravascular coagulation (a serious clotting problem that requires immediate intervention), liver disease, and the use of the anticoagulant drug warfarin.

What is normal PT INR results?

Most of the time, results are given as what is called INR (international normalized ratio). If you are not taking blood thinning medicines, such as warfarin , the normal range for your PT results is: 11 to 13.5 seconds. INR of 0.8 to 1.1.

What does it mean if my PT/INR test result is too low?

If your PT/INR test result is too low, it means that your dose of warfarin may not be enough to protect your blood from clotting. Your warfarin dose needs to be increased. On the other hand, if your PT/INR test result is too high, it means that your blood is clotting too slowly and you are at risk of bleeding.