Gastroscopy is the preferred screening and treatment for upper gastrointestinal tract pathology and does not require the use of medicated liquids to empty the bowels prior to the gastroscopy. Patients usually need to fast for 8 to 12 hours to empty the stomach before the gastroscopy is performed. The presence of food residue in the stomach is usually detrimental to the visualization of lesions during a gastroscopy, which usually needs to be performed on an empty stomach. Gastroscopy is a procedure in which the gastroscope is inserted deep into the stomach to scrutinize the gastric mucosa. At this time, it is necessary to keep the stomach free of residue, so as not to obscure the gastric mucosa with residue, thus affecting the results of the gastroscopy. If gastroenteroscopy is done at the same time, the intestines need to be cleaned. If you drink the medicine and don’t pull, you can clean the intestines by enema. If you have a physical disease or have taken anticoagulant or blood-activating drugs before gastroscopy, you need to inform your doctor in time. Please follow the doctor’s instructions.