Aspirin has an antithrombotic effect when used in small doses. The mechanism of antithrombosis is mainly manifested in irreversible inhibition of cyclooxygenase synthesis, reduction of prostaglandin production and inhibition of platelet thromboxane A2 production, thus inhibiting platelet adhesion and aggregation and affecting the formation of thrombus. Therefore, this drug is often used clinically for the treatment and prevention of cardiovascular diseases such as coronary atherosclerotic heart disease, transient ischemic attack and cerebral thrombosis. After taking aspirin for about a week, the platelets in the blood are basically completely controlled, and its effect can last for about a week. Therefore, the platelet aggregation function in the blood will not be restored until the new platelets in the bone marrow replace the inhibited platelets after a week of stopping the drug. Clinically, avoid using it in combination with anticoagulant drugs such as heparin to avoid increasing the risk of bleeding.