Gastroscopy is not harmful to the body, because gastroscopy can detect many gastrointestinal diseases, such as chronic gastritis, gastric ulcer, gastric cancer and other early diseases, and now gastroscopy is carried out more, side effects, adverse reactions are very rare, as long as the patient’s body base situation is better, can tolerate gastroscopy. However, there are the following precautions before gastroscopy: first, perfect electrocardiogram, if the patient suffers from arrhythmia, acute myocardial infarction and other diseases, it is not suitable for gastroscopy, and it is necessary to perfect the electrocardiogram to exclude these diseases. Secondly, liver and kidney function, also need to perfect the examination of liver and kidney function, if the patient’s transaminase is high and there is liver function damage, it may also not be suitable for gastroscopy, it needs to be comprehensively evaluated by the doctor, and it is not harmful to the body to do the gastroscopy after eliminating some of the above risks.