The complication that the nurse will most probably anticipate is severe bleeding and thrombus formation. Venous thromboembolism is a condition that involves the formation of blood clots. These blood clots could dangerously travel to the lungs and block some of the blood supply. Warfarin is a drug prescribed as an anticoagulant since it causes the blood to be thinner. It has been proven that warfarin can interact with some herbal medications. Depending on the type of herbal medications, this interaction can inhibit and enhance warfarin's action. In the case of enhancement, severe bleeding could occur, while inhibition of warfarin's action could lead to thrombosis (formation of blood clots).