What is inr lab

Heart Rhythm Society. Patient Information, International Normalized Ratio. University of Alabama at Birmingham Coagulation Service. Bleeding Guidelines. Thomas, Clayton L. Pagana, Kathleen D. University Pathology Consortium [On-line handbook]. Northwest Cardiovascular Associates, S. Brose, M. Prothrombin time PT. MedlinePlus Medical Encyclopedia [On-line information]. Brooke Huffman, G. Management of Patients Taking Warfarin.

Walling, A. Miller, K September Sadovsky, R. Horton, J. Warfarin Therapy: Evolving Strategies in Anticoagulation. PT and INR. Nome formal.

Prothrombin Time and International Normalized Ratio. At a Glance. Why Get Tested? These include bleeding, infection, bruising, and feeling lightheaded. When the needle pricks your arm or hand, you may feel a slight sting or pain. Afterward, the site may be sore. Certain foods and any medicines you take may affect your results, especially if you take warfarin, heparin, or other anti-clotting medicines or are being treated for liver disease with vitamin K.

It's very important to follow your healthcare provider's instructions for having this test. You may be asked to stop eating foods that are high in vitamin K before this test. Be sure your healthcare provider knows about all medicines, herbs, vitamins, and supplements you are taking.

This includes medicines that don't need a prescription and any illicit drugs you may use. Search Encyclopedia. International Normalized Ratio Does this test have other names? INR, standardized prothrombin time What is this test? No special preparation is needed.

However, many medicines, foods and illnesses can affect this test. So tell your doctor about any medicines and supplements you are taking, as well as any changes in your diet. When you are having warfarin treatment, your doctor will probably have a target INR for you. If your INR is too high, it might mean your blood clots too slowly, and there is a risk of bleeding. If your INR is too low, it might mean you have a risk of developing a blood clot.

If you are not having warfarin treatment and your INR is higher than normal, you might need further tests. You can also read more about blood tests in general. Visit our Guide to blood testing to learn more about blood tests in general with information such as:.

Learn more here about the development and quality assurance of healthdirect content. Describes how the prothrombin time PT test is used, why the PT test is done, and what the results might mean. Read more on HealthEngine website. Description of factors involved in coagulation of the blood, factors measured in the investigation of clotting disorders. The international normalised ratio INR is a laboratory measurement used to determine the effects of oral anticoagulants such as warfarin on the body's blood clotting.

An abnormal prothrombin time is often caused by liver disease or injury or by treatment with blood thinners. The U. If you need a PT test frequently and for a long time, you may want to ask your doctor if this home test is an option for you.

In some cases, the health professional will take a sample of blood from your fingertip instead of your vein. For a finger stick blood test, the health professional will clean your hand, use a lancet to puncture the skin, and place a small tube on the puncture site to collect your blood. When a blood sample is taken, you may feel nothing at all from the needle. Or you might feel a quick sting or pinch. There is very little chance of having a problem from this test. When a blood sample is taken, a small bruise may form at the site.

Each lab has a different range for what's normal. Your lab report should show the range that your lab uses for each test. The normal range is just a guide. Your doctor will also look at your results based on your age, health, and other factors. A value that isn't in the normal range may still be normal for you. A method of standardizing prothrombin time results, called the international normalized ratio INR system, has been developed so the results among labs using different test methods can be understood in the same way.

Using the INR system, treatment with warfarin Coumadin will be the same.