Targeted application of drugs to block the activation of coagulation factors in the process of thrombosis is anticoagulation therapy. In human physiology, thrombus formation and dissolution are in balance with each other. Once venous thrombosis occurs, the body’s coagulation process takes over. Therefore, the targeted application of drugs to block the process of thrombosis in the activation of coagulation factors this link is anticoagulation therapy. Commonly used anticoagulant drugs include three categories: heparin, coumarin drugs and antiplatelet drugs. Heparin is a short-acting anticoagulant that is mostly injectable and is generally used for anticoagulation during surgery or for the treatment of acute thrombotic diseases, such as low molecular heparin. Coumarin drugs, represented by warfarin, are mostly oral drugs, long-acting anticoagulants, mostly used for prevention of recurrence after thrombosis treatment or prevention of vascular occlusion after various kinds of revascularization surgeries. Antiplatelet drugs, commonly aspirin, clopidogrel, etc., have the function of antiplatelet aggregation and adhesion, which can prevent cerebral thrombosis, coronary heart disease, myocardial infarction and other diseases. Regardless of which type of anticoagulant drug is applied, there is a danger that the dose is too small to achieve the anticoagulant effect, and too large a dose will greatly increase bleeding complications. Therefore, in the process of application, it is necessary to follow the doctor’s instructions to take and monitor the changes in blood coagulation function in order to adjust the dose of the drug.