For most healthy adults, it's usually between 24 and 72 hours. After you eat, it takes about six to eight hours for food to pass through your stomach and small intestine. Food then enters your large intestine (colon) for further digestion and absorption of water.
The prothrombin time (PT) â along with its derived measures of prothrombin ratio (PR) and international normalized ratio (INR) â are assays evaluating the extrinsic pathway of coagulation.This test is also called ProTime INR and PT/INR.They are used to determine the clotting tendency of blood, in the measure of warfarin dosage, liver damage, and vitamin K status. PT measures factors I (fibrinogen) , II (prothrombin) , V, VII, and X.aboratory measurement [edit]. The reference range for prothrombin time depends on the analytical method used, but is usually around 12â13 seconds (results should always be interpreted using the reference range from the laboratory that performed the test), and the INR in absence of anticoagulation therapy is 0.8-1.2.
This ratio â which allows for easier comparisons of test results from different laboratories â is used if you take blood-thinning medications. 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.