INR is not a drug itself, but rather a standardized measurement used to assess the effectiveness of the anticoagulant drug warfarin. It stands for International Normalized Ratio.
In more detail:
The INR is a calculation based on the Prothrombin Time (PT), a blood test that measures how quickly your blood clots. When a patient is prescribed warfarin (a vitamin K antagonist), the INR is monitored regularly to ensure the drug is working effectively to prevent blood clots without causing excessive bleeding.
- Warfarin: This is an anticoagulant drug (blood thinner) that reduces the formation of blood clots.
- Prothrombin Time (PT): This is a blood test that measures the time it takes for blood to clot.
- International Normalized Ratio (INR): This is a calculation that standardizes the PT results, making it easier for doctors to compare results from different laboratories.
The goal of warfarin therapy is to keep the INR within a specific therapeutic range, typically between 2.0 and 3.0 for most conditions. This range can vary depending on the individual's condition and medical history.
- Subtherapeutic INR (below the target range): Increases the risk of blood clots.
- Supratherapeutic INR (above the target range): Increases the risk of bleeding.
Therefore, INR is a measure, not a medication, and it helps clinicians adjust warfarin dosage to optimize anticoagulation therapy.
