Coagulation tests or PT prothrombin time test

The international ratio of INR has been calculated from the PT test results and is used to evaluate the effectiveness of anticoagulants or diluents such as warfarin, coumidine. This test measures the time when a person's blood clots after bleeding. Often, with the PT test, another test called PTT or partial thromboplastin test is performed. The two tests together evaluate the amount and function of coagulation proteins known as coagulation factors. These coagulation factors control most of the body's blood clotting process. The existence of each one for the proper and timely formation of clots is very necessary and of great importance.

When do you need this test?
In addition to the need for this test when taking anticoagulant drugs, there are other things that require you to do this test. Some of these include:

Bruising or bleeding
Bleeding gums
There is a blood clot in the vein or artery
Chronic liver disease that affects the body's normal conditions
A very dangerous condition called a diffuse intravascular clot or DIC that increases the chance of bleeding and blood clots due to inappropriate use of coagulation factors.
These tests are performed before surgery with high bleeding probability or in people with bleeding history.
PT Test Values:
In people taking anticoagulants such as warfarin, the result of this test will be given as INR values. In these people, the two to three INRs should be based on the need for a blood thinner. In people who are at high risk of developing blood clots, there will be a need for a higher INR of about 2.5 to 3.5.

The range of results for this test will vary somewhat in each lab. The people tested for this test would be better off for a more accurate evaluation of their test result values ​​compared to the normal range of the lab.

Interpretation of test results PT:
PT result with long time and normal PTT: With the possibility of liver disease, reduced vitamin K, reduced or defective coagulation factors, the possibility of chronic intracerebral flora formation is associated with warfarin anticoagulant therapy.

The result is a normal PT with long PTT: the probability of decreasing or defective coagulation factors, van Wilberg disease, the presence of anticoagulants due to lupus, the immune system stimulated against some coagulation factors.

Long-term PT and PTT: severe liver disease, excessive use of warfarin, excessive vascular flora.

What preparations are required for this test?
Some of the ingredients, such as alcohol, can affect the outcome of the PT and the INR test.
Some antibiotics can increase the PT and INR outcomes.
Barbiturates, birth control pills, and anti-hormone replacement therapy (HRT) and vitamin K (present in a multivitamin or nutritional supplement) may decrease PT results.
Certain foods like beef, green tea, broccoli, chickpea, cabbage, turnip, and soy products contain large amounts of vitamin K and can affect the result of PT.
In people taking anticoagulants, it is recommended to take an anticoagulant dose every day before taking it.
Although there is no specific physical fitness for blood testing this test is required. Finally, it's better to follow the above to make sure that the PT test and your PTT test are reliable and that your doctor can prescribe the best treatment based on your values.


You can simply use the membership in Trita and log into the user area of ​​the Intelligent Physician System, you will also be able to test your protrombin test in Trita and interpret the amount in your test without the need for a physician. Please refer to the Blood Tests section at the beginning of the study.

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Fatemeh Ghorbani

Fatemeh Ghorbani

فاطمه قربانی هستم، لیسانس ژنتیک، به علوم نوین پزشکی و ایمونولوژی علاقمندم. از شما دوست گرامی بخاطر مطالعه این مقاله و همچنین مجموعه تریتا بخاطر فرصت انتشار مطالبم در راستای کمک به ارتقای دانش کمال تشکر دارم. شاد باشید و سلامت

my name is Fatemeh Ghorbani, I have a B.S in genetics and interested in immunology and medical science. I believe that, even into the smallest acts, should be put our heart, mind and soul. Thank you for reading my article