INR
For Warfarin Patients
An INR test measures the time for the blood to clot. It is also known as prothrombin time, or PT. Prothrombin is a protein produced by your liver. It is one of many factors in your blood that help it to clot appropriately.
Most often, the prothrombin time is monitored if you are taking the blood-thinning medication warfarin. In this situation, the prothrombin time is expressed as an international normalized ratio (INR). The INR can also be used to check if you have a blood clotting problem. Your doctor may recommend a prothrombin time test prior to surgery if there is any concern about your blood’s ability to clot. If your doctor suspects you have other health issues, such as liver problems or a bleeding disorder, you might need additional testing to confirm your condition.
In healthy people an INR of 1.1 or below is considered normal. An INR range of 2.0 to 3.0 is generally an effective therapeutic range for people taking warfarin for disorders such as atrial fibrillation or a blood clot in the leg or lung. In certain situations, such as having a mechanical heart valve, you might need a slightly higher INR.
When the INR is higher than the recommended range, it means that your blood clots more slowly than desired, and a lower INR means your blood clots more quickly than desired.
At Remedies our INR Testing service provides fast, reliable results.
How it works:
- Simple fingerstick test – The pharmacist will take a sample of your blood with a finger stick.
- Accurate INR results in one minute – The pharmacist will give you the test result within minutes, while you are still in the exam room.
Clotting too slowly
Blood that clots too slowly can be caused by:
- Blood-thinning medications
- Liver problems
- Inadequate levels of proteins that cause blood to clot
- Vitamin K deficiency
- Other substances in your blood that hinder the work of clotting factors
Clotting too fast
Blood that clots too quickly can be caused by:
- Supplements that contain vitamin K
- High intake of foods that contain vitamin K, such as liver, broccoli, chickpeas, green tea, kale, turnip greens and products that contain soybeans
- Estrogen-containing medications, such as birth control pills and hormone replacement therapy