A prothrombin time is a crucial lab value when monitoring anticoagulant therapy. It is also used in the screening process for fibrinogen and clotting factor deficiencies, liver function and to evaluate Vitamin K status.
Test Preparation For Optimal Results:
If possible, have the lab collected early in the morning or shortly after waking. For comparison purposes, have subsequent labs collected close to the same time.
Disclaimer: Your health care provider should evaluate a deviation from normal ranges.