Medical Devices

Prothrombin

What does this test do? This is a home-use test kit to measure how long it takes for your blood to clot.

What type of test is this? This is a quantitative test -- you find out the length of time it takes your blood to clot.

Why should you do this test? If you take blood-thinning drugs such as Coumadin or Warfarin, you may need to test you blood regularly to make sure it clots properly. Doctors often prescribe these drugs to prevent blood clots in patients who have artificial heart valves, irregular heart beats or inherited clotting tendencies. Your doctor will prescribe this test for you if you need to do it.

How often should you do this test? You should follow your doctor's instructions about how often you do this test. Your doctor may ask you to use the results to adjust the amount of drugs you to take to control your blood clotting. Never change the drugs you take without your doctor's permission.

How do you do this test? You prick your finger with a lancet to get a drop of blood. Place the drop of blood on a test strip or cartridge, and insert it into your test meter. Your meter will measure how long it takes for the blood to form a clot and how much anticoagulant effect there is.

How can you make sure your meter works properly? Your meter has some built-in features that allow it to test itself and detect problems in its operation. Your meter comes with sample solutions to use instead of your blood to assure that it is working properly. Look in your meter's operator manual to see how to check on its accuracy.

Take your meter with you to your doctor's office. Have your doctor watch you do your testing. Your doctor may want to take a sample of your blood and compare the clotting time of that sample with the time your meter gives. If the value you get matches your doctor's value, that you will know your meter is working well and that you are doing the test correctly.

Page Last Updated: 06/05/2014
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