If you were tested because you are on warfarin, the results would most likely be in the form of INR levels (International Normalised Ratio). INR levels are often used to compare results from different laboratories and make test procedures simpler.
For healthy individuals, Normal INR: 0.9 – 1.3
Normal INR values in people taking anticoagulant medicine: 2.0 – 3.0
High risk of bleeding: >5.5
If INR values are less than 0.5, the person has a high risk of blood clotting.
INR values are useful to adjust the dosage of anticoagulants and how well these medicines are working to prevent blood clots. By determining the INR values, the doctor will determine how these medicines are working and how this is effective in preventing a blood clot.
For patients on anticoagulant medicine, the dosage is reduced if the INR value is 4, which is more than normal.
If INR value is less than normal, then the dosage of medicine is increased.
If you do not take warfarin, your results may be in the form of INR levels or the time it takes for your blood sample to clot (prothrombin time).
In normal people, prothrombin time: 10-15 seconds. Whereas, prothrombin time for people taking anticoagulant medicine: 22-35 seconds
Critical value: >65 seconds. These people should consult a doctor.