With the improvement of gastroscopy equipment and endoscopist technology, now the new electronic gastroscope has been improved a lot, its mirror body is thin, soft, good compliance, coupled with the doctor’s proper operation, a few minutes to complete the examination, the patient only feel nausea, and will not have too much pain. In recent years, the development of painless gastroscopy, can make the patient in the painless “sleep” in the completion of the examination, by many patients to do gastroscopy favored. Many patients contacted in the clinic requested painless gastroscopy because “Doctor, I am afraid of pain, I can’t tolerate ordinary gastroscopy”. So is it true that all patients who are “afraid of pain” can choose painless gastroscopy? In fact, although painless gastroscopy has the advantage of painless, but not all patients with gastric disease can choose painless gastroscopy. Commonly used medications for painless gastroscopy are isoproterenol and midazolam. Isoproterenol is a fast-acting intravenous sedative with rapid recovery, short duration of action and rapid awakening. The adverse effects of isoproterenol are mild and transient, and a small number of patients may experience a drop in blood pressure, slow heart rate, slowing of the whistle, hypoxemia and other inhibition of the whistle circulation, which may pose a certain risk to patients with severe hypertension, heart disease and cerebrovascular disease. Therefore, patients with the following conditions are generally not recommended to choose painless gastroscopy: 1, suffering from bradycardia, severe hypertension, cardiovascular and cerebrovascular diseases should not be painless gastroscopy; 2, certain diseases such as bronchitis, gastric ulcer or gastric cancer and gastric retention, acute upper gastrointestinal hemorrhage gastric blood retention, liquid reflux is easy to cause asphyxiation, also should not be painless gastroscopy; 3, severe snoring and over-obese patients can also be asphyxiated during the examination, painless gastroscopy should be carefully selected; 4, pregnant women and breastfeeding women should not choose painless endoscopy.