Vitamin K Antagonists
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Overview
Vitamin K antagonists are oral anticoagulants that prevent blood clot formation by inhibiting vitamin K-dependent clotting factors. Warfarin is the most commonly used drug in this class.
How do vitamin k antagonists work?
These drugs inhibit the enzyme vitamin K epoxide reductase, which is necessary for the recycling of vitamin K. This reduces the synthesis of clotting factors II, VII, IX, and X, thereby slowing the coagulation cascade.
Drugs in this class
- Warfarin (Coumadin, Jantoven)