Coumadin is an anticoagulant drug that acts by hindering the creation of vitamin K-dependent coagulation factors. It leads to the decrease in the activities of Factors VII, IX, X and II. This decrease is reliant upon the dose given. Anticoagulants have no immediate impact on a formed thrombus, nor do they reverse damage due to ischemia. It prevents further coagulation and prevents thromboembolic complications.