Revealing the secrets of aspirin: These key knowledge will help you use the medicine safely!

Author: Qin Lingling Beijing Chaoyang Hospital Affiliated to Capital Medical University

Reviewer: Zhao Lin, Chief Physician, Beijing Chaoyang Hospital, Capital Medical University

Aspirin is a century-old "old medicine" and is known as one of the three classic drugs in the history of medicine, along with penicillin and diazepam. When aspirin first came out, it was used as an antipyretic and analgesic. But later studies found that this small pill has a great effect, and many scientific evidences support that aspirin is very helpful for cardiovascular diseases. Aspirin has become a key drug for the prevention and treatment of cardiovascular and cerebrovascular diseases.

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Anti-thrombotic means preventing the formation of blood clots. In layman's terms, it is to prevent blood from becoming viscous. For patients with coronary heart disease, taking aspirin has become a "must-have" every day. Although aspirin is a commonly used drug for treating patients with coronary heart disease, in clinical work, some patients develop serious complications from taking aspirin without knowing it, resulting in re-hospitalization.

Next, I will summarize the precautions when taking aspirin, hoping that it will be helpful to people who take aspirin.

1. The best time to take aspirin

Aspirin is most effective when taken in the morning, because morning is a high-risk time for sudden cardiovascular and cerebrovascular diseases. In clinical work, I have seen some patients take it before breakfast and some patients take it after breakfast. So, should aspirin be taken before or after breakfast?

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There are two types of aspirin we commonly use: enteric-coated aspirin tablets and regular aspirin preparations.

1. Enteric-coated aspirin tablets : This is the type taken by most patients with coronary heart disease. Enteric-coated aspirin tablets should be taken before breakfast for the following reasons.

(1) This type of enteric-coated tablet is acid-resistant but not alkali-resistant. The acidity in the stomach is strong when the stomach is empty, which can ensure that the "outer coating" of the enteric-coated tablet is not eroded. In addition, when taken at this time, the stomach empties faster, which can ensure that the time the tablet stays in the stomach is as short as possible.

(2) If taken after a meal, food residues will constantly rub against the enteric-coated aspirin tablets due to the movement of the stomach, destroying the "outer coating" of the enteric-coated tablets, causing aspirin to be released prematurely and causing damage to the gastric mucosa.

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At the same time, it is important to remind patients who take aspirin that enteric-coated aspirin tablets should not be broken apart for consumption. Once broken apart, the "outer coat" on the surface of the drug will be destroyed, thus losing its function of protecting the gastric mucosa.

The conventional dose of enteric-coated aspirin tablets is 100 mg. Some patients need to reduce the dose due to intolerance. Therefore, it is necessary to choose a more appropriate dose of ordinary aspirin preparation.

2. Ordinary aspirin should be taken after breakfast. Mixing food with medicine can reduce the damage of aspirin to the gastric mucosa.

How long should aspirin be taken?

Antithrombotic therapy is the first treatment for patients with coronary heart disease. Once diagnosed with coronary heart disease, it means that patients need to take antithrombotic drugs for life. Aspirin is the cornerstone of antiplatelet therapy. For patients with acute coronary syndrome and coronary stent implantation, an antithrombotic drug is also needed on this basis. Taking two drugs at the same time is called "dual antiplatelet therapy", or "dual antiplatelet therapy" for short. The latest evidence-based medicine recommends two antithrombotic drugs: ticagrelor tablets and clopidogrel sulfate tablets.

Both domestic and international guidelines recommend that "dual-antibody" treatment be continued for 6 to 12 months. Premature discontinuation of "dual-antibody" treatment will increase the risk of cardiovascular death or myocardial infarction. After the end of "dual-antibody" treatment, it is necessary to switch to "single-antibody" treatment, that is, only take one antiplatelet drug. Most patients will take aspirin. If intolerance occurs, the doctor will adjust it to ticagrelor tablets or clopidogrel sulfate tablets according to the individual situation of the patient. "Single-antibody" treatment will accompany patients with coronary heart disease throughout their lives.

While taking aspirin, some patients may need to undergo invasive procedures such as surgery and tooth extraction. Since antithrombotic treatment can prolong blood coagulation time and make it difficult for wounds to stop bleeding, the doctor will ask the patient to stop taking aspirin for about 7 days before the procedure. The aspirin in the body will be metabolized after about 7 days. In this case, the patient must tell the doctor that he or she has coronary heart disease. The doctor will adjust to other drugs based on the actual situation, such as subcutaneous injection of low molecular weight heparin. The metabolism time of low molecular weight heparin in the body is 12 hours, which is shorter than the metabolism time of aspirin. Generally, invasive procedures can be performed after stopping the drug for more than 12 hours.

Therefore, no matter when and where, patients with coronary heart disease should strictly follow the doctor's instructions to take aspirin, and avoid stopping or changing the medicine without authorization. If it is necessary to stop the medicine, it should also be replaced according to the requirements of professional doctors.

3. What are the adverse reactions of aspirin?

The adverse reactions of aspirin include gastrointestinal reactions such as heartburn, nausea, and vomiting, allergic reactions in the respiratory tract, skin, and other parts, as well as hypoglycemia and abnormal liver function. The probability of the above adverse reactions is not high. However, we need to remind everyone that there is a more dangerous adverse reaction to taking aspirin - bleeding.

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We know that patients with coronary heart disease take enteric-coated aspirin tablets mainly to exert its antiplatelet effect, thereby preventing thrombosis. However, it is the antiplatelet effect of aspirin that leads to the risk of bleeding.

Before taking aspirin, the doctor will fully evaluate the patient for coagulation abnormalities through laboratory tests. Therefore, bleeding is rare in patients, so there is no need to worry. It is important to learn to recognize the risk of bleeding, and if you find any signs of bleeding, you should seek medical attention immediately. Under the guidance of the doctor, you can properly handle this problem by adjusting the use of medication appropriately.

So, what are the common manifestations of bleeding? First of all, the most easily noticed are nose bleeding and bleeding gums when brushing teeth in the morning.

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Secondly, watch for bruises and bleeding spots on the skin after minor or no collisions. These are signs of bleeding that need attention.

It is difficult for patients to directly detect internal bleeding. If the stool becomes dark and tarry, it may be a sign of gastrointestinal bleeding. Therefore, patients taking aspirin should carefully observe the color of stool after each bowel movement before flushing! If you have pale complexion, cold hands and feet, and general weakness, you should be highly alert to the occurrence of anemia and go to the hospital immediately.

So, is the adverse reaction of bleeding common? The results of relevant studies show that fatal bleeding will hardly occur if the dose of aspirin does not exceed 100 mg per day. Therefore, as long as everyone understands the early signs of bleeding, there is no need to worry too much.

In short, if we are familiar with and follow the precautions of taking aspirin, it will become our "right-hand man" to effectively fight against coronary heart disease.