The INR (International Normalized Ratio) test is a standardized measure of blood clotting time, primarily used to monitor the effectiveness of anticoagulant medications such as warfarin. By adjusting the results of the Prothrombin Time (PT) test and minimizing variations between laboratories (due to differences in measurement methods or chemical reagents), INR provides a more accurate assessment of bleeding risk or clot formation. In healthy individuals, the INR is typically between 0.9 and 1.1. However, for patients on warfarin therapy, the therapeutic INR range is often set between 2.0 and 3.0 or higher, depending on the condition (such as atrial fibrillation, deep vein thrombosis, or the presence of mechanical heart valves). Elevated INR levels indicate a risk of bleeding, while low levels suggest a risk of clot formation. This test is regularly performed to adjust medication dosage and prevent serious complications. Interpretation of results should take into account the patient’s medical history and clinical guidelines.
