There are two aspects of painless gastroscopy precautions: pre-gastroscopy and post-gastroscopy. 1. Before painless gastroscopy: (1) Accurate examination and exclusion of contraindications, pregnant women and lactating women are not recommended to do painless gastroscopy. (2) Fasting and water fasting should be satisfied for 4-6 hours, and longer fasting and water fasting is recommended for the elderly and patients with poor gastric motility. (3) Because painless gastroscopy needs anesthesia, there may be dizziness after waking up, so you can’t do gastroscopy alone and need to be accompanied by someone. 2. After painless gastroscopy: (1) Avoid driving and engaging in high altitude work, such as installing air conditioners. (2) pay attention to 2 hours before the intake of warm fluids, some patients to take more biopsies, will also be appropriate to extend the time of water intake, eat warm and cool fluids, avoid overheating, too hot, to prevent re-bleeding. (3) Pay attention to whether there are symptoms of hypoglycemia such as dizziness, panic, etc. Pay attention to detecting whether there are symptoms of black stools, bright red stools, or dark red stools, and if such symptoms occur, they should go to the Emergency Department in time to seek medical treatment.