Low molecular heparin sodium has anticoagulant and antithrombotic effects and is mainly used in hemodialysis or hemofiltration to prevent blood clotting in extracorporeal circulation and to prevent the formation of thrombus. It can also be used in patients with coronary artery disease, angina pectoris, especially acute myocardial infarction. It can also be used in patients with cerebrovascular disease and in patients who are bedridden for long periods of time, and subcutaneously for the prevention of thrombosis. Low molecular heparin sodium is usually injected subcutaneously twice a day in clinical applications. During the process of application, adverse reactions may occur, including local bleeding, petechiae at the injection site, allergic reactions, local skin redness, itching, rash, and occasionally thrombocytopenia, and possibly elevated transaminases.