It is possible to drink milk the day before a gastroscopy, as long as you make sure to have enough fasting time. Gastroscopy is an examination that allows direct visualization of mucosal lesions in the esophagus, stomach, oropharynx, and duodenum, and has a high degree of diagnostic accuracy for gastrointestinal disorders. Before gastroscopy, you need to maintain a fasting state, generally need to fast for 4 hours, fasting for 6-8 hours, so as not to fill the stomach with food, which will affect the field of view of the examination, and is not conducive to the observation of diseased tissues. And, fasting and water fasting will also help to avoid aspiration during painless gastroscopy. Therefore, it is possible to drink milk the day before the gastroscopy, as long as you ensure sufficient fasting time after drinking milk. Patients who need to undergo gastroscopy should actively cooperate with the doctor’s procedure and make good preparations for the gastroscopy.