Testing Details
Fasting Required: NO
Preferred Specimen: Plasma
Limitations: Expected impact by therapeutic levels (potential interference depends upon drug concentration): Warfarin: no effect; Heparin (UFH or LMWH): UFH-no effect, LMWH-normal to falsely low; Dabigatran or Argatroban (Thrombin Inhibitors): no effect or falsely low; Rivaroxaban or Apixaban (Factor Xa Inhibitors): no effect.
Reference Range(s): 175-425 mg/dL
Turnaround Time: 3 Days
Test Code: 461
