Nitroglycerin is not only a "life-saving medicine" for sudden myocardial infarction, but also a good medicine for relieving angina pectoris. Nitroglycerin can quickly exert its effects through sublingual administration, expanding coronary arteries, improving myocardial cell ischemia and hypoxia, thereby reducing the risk of worsening myocardial infarction and buying time for patients to be sent to the hospital. However, there are several misconceptions to avoid when using nitroglycerin, otherwise not only will it fail to treat the disease, but it may also worsen angina symptoms and lead to life-threatening cardiac accidents. The misconception that once one can overcome it, not taking medication is three parts poison. Taking too much medication can harm one's health, so it is advisable to avoid taking medication as much as possible. This viewpoint is reflected in many patients. The viewpoint itself is good, but some patients are overly afraid of taking medication, thinking that the life-saving drug nitroglycerin is a "strong drug" and afraid that frequent use will cause adverse reactions, so they do not take medication even when suffering from angina, thinking about "holding on for a while". But this approach is very dangerous, even endangering lives. Although nitroglycerin may have side effects such as headaches, they are within a controllable range and generally do not recur after multiple doses. Therefore, one should not joke about their health or even life just because of fear of nitroglycerin. Misconception 2: Medication follows advertisements. Due to the dependence of some patients' medication cognition on advertisements, when it comes to taking medication for angina pectoris, the first choice is not nitroglycerin, but quick acting heart saving pills, Danshen dripping pills, Xintongding, etc. They believe that this type of medicine can "quickly" relieve angina. Obviously, this group of people is not aware that nitroglycerin is the best emergency medicine for treating angina pectoris. Of course, it is not to say that quick acting heart saving pills, Danshen dripping pills, Xintongding and other drugs have no therapeutic effect. These drugs can alleviate angina pectoris, but as an emergency treatment, nitroglycerin is undoubtedly the preferred drug. Misconception 3: Discounting Dosage: The goal of taking nitroglycerin is to eliminate angina symptoms as quickly as possible and minimize the occurrence of cardiac accidents. The current problem is that some patients do not take nitroglycerin in a timely manner, and the dosage is often insufficient, failing to achieve the goal of eliminating symptoms in the shortest possible time. Nitroglycerin can take effect after sublingual administration for 2 to 3 minutes and can last for 10 to 30 minutes. If there is no effect after taking it for 5 minutes, it should be taken again. If it is still ineffective after taking it for 3 times, it should be considered as severe angina or myocardial infarction, or other diseases accompanied by chest pain. It should be sought medical treatment as soon as possible. Misconception 4: Generally, medication should be taken with water while lying in bed, but nitroglycerin should never be taken with water. Sublingual administration of nitroglycerin has an absorption rate of around 80%, and the maximum effect is usually achieved within 5 minutes after taking. Swallowing with water has a slow onset of action, and the liver has a degradation effect on it, with only about 8% of the drug components being absorbed, which greatly reduces the effectiveness of the drug. When taking nitroglycerin, there are certain postures to follow, and it is best to take it while sitting. Sitting with clothing is better than lying down or standing. Positional hypotension can cause insufficient blood supply to the brain, leading to dizziness, hypotension, and even fainting symptoms; If the medication is taken in a supine position, it may increase the burden on the heart due to increased cardiac output, thereby affecting the efficacy of the medication. Misconception 5: Dizziness after medication is due to the toxic effect of nitroglycerin on blood pressure. Therefore, some individuals may experience symptoms of low blood pressure such as dizziness and shaking after medication. This is not poisoning, and can be restored to normal as long as they lie flat for a few minutes. Misconception 6: Keep nitroglycerin bottles with you. The expiration date of nitroglycerin is affected by temperature, humidity, and light. Especially for nitroglycerin after opening, its shelf life will be significantly shortened, usually between 3 to 6 months. Therefore, nitroglycerin should be kept away from light, sealed, and preferably stored in a cool brown glass bottle to avoid direct sunlight exposure. Some people place nitroglycerin randomly and leave the bottle lid open or not tightened, which can greatly reduce its effectiveness. Some people even put pills in their underwear pockets when carrying them with them, unaware that the body temperature can cause the drugs to evaporate and become ineffective. Therefore, when taking medication, the lid should be opened and tightened as quickly as possible to prevent the pills in the bottle from coming into contact with air and shortening the expiration date. (New Society)