What is PT/INR testing?

If you've ever experienced issues with your blood, your health care provider may have conducted PT/INR testing to determine the status of your wellness. Common conditions and symptoms that may call for this procedure include:

  • Chronic anemia
  • Nosebleeds
  • Bloody stool or urine
  • Bleeding gums
  • Heavy menstruation
  • Excessive bruising

The prothrombin time (PT) test is used to determine how long it takes for your blood to clot and can confirm if you have an issue with the consistency of your blood. It may also be used to see if you require medicine that prevents abnormal blood clots. In some instances, you may undergo a PT test before surgery, such as weight loss surgery or to spot any blood issues that may cause complications during the procedure.

PTs may also be known as INR, or international normalized ratio, tests. An INR is a method of standardizing the results revealed by the PT test. This step is necessary so that, no matter which lab the results came from or what testing techniques were used, physicians can properly read and understand the information being delivered. Since the international normalized ratio system provides the same information in an easy-to-comprehend format, some labs will only provide results for the INR and exclude the PT data.

While PT/INR tests have a variety of uses, the main function of these exams is to determine if a prescribed anticoagulant drug is working properly. The anticoagulant commonly used is warfarin, which often goes by the brand name Coumadin and may be covered by your Medicare prescription drug plan. The drug treats abnormal clots that can form in the lungs and legs by thinning the blood, thereby decreasing your risk of stroke, heart attack and other serious cardiovascular conditions. Complications can arise from taking this medicine, so your doctor will order periodic PT/INR testing to make sure it's working correctly without inducing excessive bleeding and that you're taking the right dosage. You'll generally do this testing on your own at home.

Does Medicare cover PT/INR testing?
Medicare coverage for PT/INR testing done in a clinical setting is up to the discretion of your specific plan – an agent will determine if the procedure was medically necessary using a doctors note provided by your physician. Such lab work is generally covered by Medicare Part B. But, as most people conduct these tests on their own, at-home testing supplies and equipment are also covered by Medicare. As of 2008, Medicare Part B helps pay for the cost of your PT/INR equipment when used to determine how well your anticoagulants are working. The device used is a portable handheld meter that reads your coagulation levels from a small drop of blood.

How do I qualify for coverage?
To get coverage for testing either in a clinical setting or at home, you must have a condition that requires you to take warfarin, such as chronic atrial fibrillation, venous thromboembolism or a mechanical heart valve. Additionally, you must meet these four requirements to maintain coverage for in-home testing equipment:

  1. Be on the anticoagulant for at least three months before using a coagulation meter.
  2. Undergo an in-person educational program on managing your anticoagulation medication and demonstrate that you know how to accurately use the meter.
  3. Properly use the device throughout the duration of your at-home monitoring.
  4. Self-test no more than once per week.

How much will testing cost?
The price of your testing equipment varies according the the durable medical equipment manufacturer you go through. Once you have the cost of your device approved by the national health care program, Medicare Part B will take care of 80 percent, leaving you responsible for the remaining 20 percent. Medicare Part B also provides the same coverage for people who get PT/INR testing completed in a clinical setting as long as they are approved.

How can I get coverage?
To obtain coverage for a self-testing device, you must have a doctors note that specifies that you require at-home testing to monitor and manage your oral anticoagulant intake. For services rendered in a clinical environment, your doctor must specify that laboratory testing is medically necessary. The physician who writes your prescription must be a participating member of the national health care program. You can then apply for coverage and request your Coumadin testing supplies.