NCLEX-RN

Answer: D - Warfarin is an anticoagulant that works by reducing the liver’s ability to use vitamin K, which is necessary for the activation of clotting factors II, VII, IX and X. Vitamin K partly counteracts warfarin effects; therefore, consumption of foods rich in vitamin K should be avoided during warfarin therapy. Heparin is another anticoagulant, but this medication is administered parenterally. Vitamin K is the antidote for warfarin, whereas protamine sulfate is the antidote for heparin sulfate.