How fast blood clots after bleeding depends on how much of each clotting factor is in the blood.
Once activated, the PT test is measured in seconds.
With the PT test, the reference range is between 11 to 13.5 seconds if you arenoton anticoagulants.
Verywell / JR Bee
A number higher than the reference range means your blood is taking longer than usual to clot.
A number lower than the reference range means that your blood is clotting faster than normal.
There are many possible reasons why these might occur.
Other medical conditions, substances, and diseases can also affect normal blood clotting.
International Normalized Ratio (INR)
The PT test is sometimes referred to as the PT/INR test.
For people on warfarin, the reference range of values for PT/INR is 2 to 3 seconds.
With the PTT test, the reference range is between 25 and 33 seconds.
A lower PTT number means that your blood is clotting faster than normal.
There are several reasons why this might occur.
Risks and Complications
Blood draws are routine, low-risk procedures.
The PT test is useful in evaluating the effects of the anticoagulant warfarin and identifying clotting and bleeding disorders.
The international normalized ratio (INR) test ensures that PT results are standardized.
UCSF Health.Prothrombin Time (PT).
MedlinePlus.Prothrombin time test and INR (PT/INR).
NewYork-Presbyterian.Prothrombin Time (PT/INR) Test.
UCSF Health.Partial thromboplastin time (PTT).
