The main complication of anticoagulant therapy is major bleeding. Clinicians are usually aware of these side effects and are careful when managing the therapeutic range of vitamin K antagonist drugs. But major bleeding, while life-threatening, can be overlooked if there are no visible signs of bleeding. Two cases are described in which inaccurate diagnoses lead to inadequate treatment.
Keywords: Vitamin K antagonists; major bleeding; prothrombin complex concentrate.