When should aspirin and clopidogrel be taken together and when should they be taken alone?

A friend told Hua Zi that his father had been taking aspirin after suffering from coronary heart disease, but he still had a myocardial infarction some time ago. Added clopidogrel. He was very puzzled, why would there be myocardial infarction even after taking aspirin, and how long would it take for the two antiplatelet drugs?

Hua Zi said that some people have aspirin resistance, people with high risk of cardiovascular and cerebrovascular diseases, taking aspirin alone may not achieve the ideal preventive effect .

I. Antiplatelet therapy may cause drug resistance

Aspirin can inhibit cyclooxygenase on platelets, inhibit platelet aggregation and thrombosis, and is the most commonly used antiplatelet drug. However, in the process of using it, it was found that some people will develop drug resistance after taking aspirin, and still have cardiovascular and cerebrovascular diseases such as myocardial infarction and cerebral infarction.

According to relevant statistics, The probability of drug resistance with aspirin alone is about 30%. The metabolite of clopidogrel can inhibit the platelet P2Y12 receptor, and is another commonly used antiplatelet drug. The probability of drug resistance when taking clopidogrel alone is about 40%.

However, when two drugs are used in combination, they inhibit platelets through different pathways, and the probability of drug resistance is reduced to 5%. Therefore, for people with high risk of cardiovascular and cerebrovascular diseases, doctors will use two antiplatelet drugs for “double antibody” treatment.

Second, “double antibody” can only be used when the benefits outweigh the risks

Although “dual-antibody” treatment has a lower probability of drug resistance and a better prevention effect on thrombosis, it is not suitable as a routine prevention program . Because aspirin will directly damage the gastric mucosa and inhibit the production of prostaglandins; clopidogrel will inhibit the release of platelet-derived growth factor, which will weaken the repair and protection of the digestive tract mucosa.

So “Double Antibody” treatment is a double-edged sword. While preventing thrombosis, it will inevitably cause damage to the gastrointestinal mucosa, and Increased bleeding risk and is only recommended when the benefit clearly outweighs the risk.

“Double antibody” treatment is usually only used for patients with high risk of cardiovascular diseases such as acute coronary syndrome, interventional balloon dilation, cardiac stent, and cardiac bypass, which should be confirmed by a doctor according to the specific situation” The treatment time of “double antibody” varies from 1 to 18 months. For example, after balloon dilation, it usually takes 1 to 3 months, and after stenting, it usually takes 6 to 12 months.

Third, which drug to keep at the end of “double antibody” treatment

“Double antibody” therapy can achieve the strongest antiplatelet effect, but the risk of medication will also increase. After the end of the course of treatment, monotherapy should be resumed. In terms of drug retention, traditional views believe that aspirin is more effective in preventing thrombosis, but aspirin is also more harmful to the digestive tract.

Therefore, people without digestive tract disease and injury are advised to stop taking clopidogrel and keep aspirin. However, if there is gastrointestinal disease, or gastrointestinal damage has occurred, clopidogrel can also be retained and aspirin discontinued. At the same time, antacids (such as prazoles, tidines, etc.) and gastric mucosal protective agents are added to protect the gastric mucosa.

Fourth, what should be paid attention to in the treatment of “double antibody”

Choose enteric-coated tablets for aspirin, take at least half an hour before meals or on an empty stomach, Clopidogrel is recommended to be taken within 15 minutes after meals , can reduce adverse reactions and increase the effect of drugs.

The blood pressure should be controlled during the medication period, and the blood pressure should not exceed 160mmHg. It is better to control the blood pressure below 130/80mmHg, which can reduce the risk of cerebral hemorrhage.

If there is Helicobacter pylori infection, it is recommended to treat it before starting treatment, which can reduce the damage to the gastric mucosa.damage. In the process of medication, pay attention to avoid combination with other drugs with digestive tract damage, do not eat irritating diet, and people over 80 years old are not recommended to use “double antibody” treatment.

To sum up, aspirin and clopidogrel are both antiplatelet drugs, and drug resistance may occur when used alone. People at high risk of cardiovascular disease need “double antibody” treatment to effectively prevent the formation of thrombosis. However, the drug risk of “double antibody” treatment is high, and it is not recommended as a long-term preventive drug regimen. The medicine should be used under the guidance of a doctor. If you have any doubts about the medicine, please consult your doctor or pharmacist. I am Huazi, a pharmacist. Welcome to follow me and share more health knowledge.