In China, one patient is killed by cardiovascular disease every 15 seconds, and one patient is incapacitated every 22 seconds – alarming figures at the 2008 Thrombophilia Symposium. Numerous studies have confirmed that aspirin significantly reduces the risk of myocardial infarction, stroke and death by up to 50%, and is a cornerstone in the primary and secondary prevention of cardiovascular and cerebrovascular diseases. Aspirin is an evergreen in the history of medicine, having been used clinically for over 100 years, and it is still the most widely used antipyretic, analgesic and anti-inflammatory drug in the world. After oral administration, most of the drug is absorbed in the upper part of the small intestine, and most of it is quickly hydrolyzed into salicylates in the gastrointestinal tract, liver and blood, reaching peak concentration within about 6 hours. The effect of aspirin varies with the dose. Large doses (more than 4g/d) have anti-inflammatory and anti-rheumatic effects; medium doses (500mg/d~3g/d) have antipyretic and analgesic effects; while small doses (75~300mg/d) have anti-platelet effects, whose mechanism of action is mainly through the inhibition of platelet cyclooxygenase, reducing the production of thromboxane A2, thereby inhibiting the aggregation and release of platelets and reducing the formation of blood clots. Therefore, small doses of aspirin are widely used in the prevention of cardiovascular diseases, especially for primary prevention (preventing the occurrence of cardiovascular diseases) in patients with risk factors for cardiovascular diseases such as diabetes, hypertension, lack of exercise, obesity, advanced age, family history, hyperlipidemia and smoking, and for secondary prevention (preventing the recurrence of cardiovascular diseases) in patients who have already experienced cardiovascular diseases . However, healthy people without cardiovascular risk factors should not take aspirin as a preventive medicine against cardiovascular disease, because a recent study of 110,000 people in the United States showed that aspirin did not benefit these people, but increased the risk of bleeding. Previous data have recommended a wide range of dose sizes, leaving people in the dark. This is because aspirin has an anti-platelet coagulation effect from 5mg, and by 100mg platelets are fully inhibited, with an increased risk of bleeding at over 325mg or 500mg. Therefore, experts recommend that it should be treated with long-term oral aspirin 75-150 mg per day, and this small dose of aspirin is considered to be the most effective and least toxic. The most common adverse effect of aspirin is damage to the gastric mucosa, which manifests itself as gastrointestinal reactions such as nausea, vomiting, upper abdominal discomfort or pain, and in rare cases, gastrointestinal bleeding or ulcers, associated with increasing doses. High doses of aspirin double the risk of gastrointestinal bleeding, but fatal bleeding is extremely rare. Therefore, aspirin is now mostly used in enteric tablets or biaxin, so that it enters the intestinal tract before absorption begins, and is best taken after meals to minimize gastrointestinal adverse reactions; aspirin can also be used with caution in patients with gastrointestinal disease under the protection of gastric mucosal protective drugs. Other rare adverse effects include bronchospastic hypersensitivity reactions, skin hypersensitivity reactions, and hepatic and renal impairment. For patients who are unable to use aspirin due to these adverse effects, clopidogrel (Bolivar/Tega) or ticlopidine (Raltegravir) can be used instead; for patients at high risk of cardiovascular disease, a combination of both can be used to enhance the antiplatelet effect. In clinical practice, lifelong use of low-dose aspirin is recommended, avoiding intermittent use at intervals of more than 2 days. Abrupt discontinuation has been shown to result in a significant increase in cardiovascular events. In surgical patients, it used to be considered appropriate to discontinue the drug for more than 10 days prior to surgery. Today, there is a different answer to this question: it is necessary to consider the benefits and risks for each individual. For example, in elderly people with heart disease, it is not recommended to stop medication at the time of surgery. The risk of bleeding from minor surgery such as prostatectomy, oral surgery or superficial skin surgery is lower than the risk of a cardiovascular event without aspirin. Even when coronary artery bypass surgery was performed while aspirin was continued, no other complications occurred. Clinical experience suggests that discontinuing aspirin 48 hours prior to surgery is sufficient.