Warfarin Overdose in an Adolescent Not Dependent on Anticoagulation: Reversal Strategy and Kinetics

Warfarin induces coagulopathy. Guidelines protocolize reversal of supratherapeutic international normalized ratio (INR) in patients dependent on anticoagulation, but practices vary for reversing warfarin-induced coagulopathy after overdose in non-warfarin-dependent patients.This is the report of a 15-year-old female who ingested her father's warfarin (100-200 mg) in a self-harm attempt. At hour 24 post-ingestion, her INR was 2.00 and she was admitted for monitoring. Reversal of coagulopathy was initially deferred pending the INR trend. The INR was 5.10 at hour 60 and 2.5 mg oral vitamin KA restrictive approach to coagulopathy reversal in non-warfarin-dependent patients with intentional warfarin overdose may result in worsening coagulopathy, bleeding, and lengthy hospital stay. Given the risk for significant, prolonged coagulopathy, these patients should be treated early with VK1, with subsequent serial INR monitoring and probable additional VK1 dosing. Delayed peak warfarin concentrations support consideration of gastrointestinal decontamination in late presenters.