INR: what it is, what it is for and when it is normal

The INR is a test that evaluates blood clotting and is indicated to identify clotting problems, monitor treatment with anticoagulants, assess the risk of bleeding and liver function.

When the INR is high it means that the blood is thinner than normal and, therefore, symptoms such as bleeding from the nose or gums, vomiting or urine with blood and purple spots on the body may appear, which tend to appear without an apparent cause.

In case of changes in the INR test, it is recommended to consult a hematologist or general practitioner, especially if bleeding occurs. In cases where the person uses anticoagulants, the doctor may recommend adjusting the dose of the medication.

What is it for

The INR exam is indicated for:

• Identify blood clotting problems;
• Monitor treatment with anticoagulants such as warfarin;
• Check the risk of bleeding;
• Assess liver function.

Furthermore, the results of the INR test help the doctor to adjust the dose of medication during treatment with anticoagulants in order to avoid complications such as bleeding and prevent thrombosis. Find out the main precautions during treatment with anticoagulants.

Difference between TP and INR

PT (prothrombin time) is a test that measures the time, in seconds, that it takes for a person’s blood to clot after adding thromboplastin to the collected blood sample. Understand better what TP is and what it is for.

The INR test is based on the PT result, being calculated as a proportion between the person’s PT and the standard PT used by the laboratory.

Normal INR value

The normal INR ranges from 0.8 to 1.0 in healthy people. However, when taking anticoagulants, INR values ​​tend to be higher, generally between 2.0 and 3.0, without being considered a problem.

Especially for people who use anticoagulants, ideal INR values ​​vary according to the medical condition being treated, and it is important to consult a hematologist or general practitioner and carry out treatment according to their instructions.

For example, a person who has had a venous thrombosis may need to have an INR between 2.0 and 3.0. If a person has a mechanical valve in their heart, the ideal INR may be 3.0.

If you want to make an appointment, you can find the hematologist closest to you using the tool below:

What does INR less than 2.0 mean?

An INR less than 2.0 may indicate that treatment with anticoagulants is not sufficient to prevent blood clotting. In people who do not use these medications, INR values ​​between 1.1 and 1.9 may indicate a greater risk of bleeding.

Furthermore, values ​​below 0.8 in healthy people may mean a greater risk of clot formation.

Signs that your INR is high

Signs that your INR is high include:

• Bleeding from wounds that takes time to stop;
• Nose bleeding;
• Vomiting with blood or similar to coffee grounds;
• Gums bleeding when brushing teeth;
• Purple spots on parts of the body with no apparent cause;
• Reddish urine or visible blood.

In case of signs of high INR, it is important to consult a doctor. Furthermore, if the bleeding is severe or symptoms such as drowsiness and low blood pressure appear, it is recommended to go to an emergency room for evaluation.