Prothrombin time (PT) | p t value
PTismeasuredinseconds.Mostofthetime,resultsarealsogivenaswhatiscalledINR(internationalnormalizedratio).Ifyouarenottakingbloodthinningmedicines,suchaswarfarin,thenormalrangeforyourresultsis:PTof11to13.5secondsINRof0.8to1.1Ifyouaretakingwarfarintopreventbloodclots,yourproviderwillmostlikelychoosetokeepyourINRfrom2.0to3.0.Askyourproviderwhatresultisrightforyou.NormalvalueforPTrangesmayvaryslightlyamongdifferentlaboratories.Somelabsusedifferentmeasurementsortestdifferentsamples.
PT is measured in seconds. Most of the time, results are also 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 results is:
PT of 11 to 13.5 secondsINR of 0.8 to 1.1If you are taking warfarin to prevent blood clots, your provider will most likely choose to keep your INR from 2.0 to 3.0.
Ask your provider what result is right for you.
Normal value for PT ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples.