When your baby suddenly vomits at night, you should let your baby change to a side-lying position to facilitate the flow of vomit, and pat your baby’s back with moderate force. This situation is considered gastroesophageal reflux, gastrointestinal flu, acute gastritis, intussusception and other diseases, it is recommended to go to the hospital, clear causes after treatment. 1, gastroesophageal reflux: infants and young children gastrointestinal function is not well developed, lying down at night sleeping position is more likely to cause gastroesophageal reflux, manifested as a sudden vomiting when sleeping. Parents are advised to adjust the baby’s sleeping position, slightly elevate the upper body 30 degrees, the best position of the former prone to relieve the symptoms of vomiting; adjust the feeding method, food should not be too thick or too thin, a small number of meals, avoid eating irritating food; 2, gastrointestinal cold: mostly triggered by external stimuli, such as cold and warm weather changes, poor diet, etc., mostly manifested as abdominal distension, nausea, abdominal pain, vomiting, diarrhea and other cold symptoms, vomiting can also occur alone. Vomiting may also occur alone. If the symptoms are severe, it is recommended to take oral medications such as Nimesulide and montelukast as prescribed by the doctor. Usually pay attention to daily care, drink more water, eat more fresh fruits and vegetables and easy to digest food, keep the indoor air flowing, in case of climate change in time to increase or decrease clothing; 3, acute gastritis: baby eating unclean food during the day, in addition to sleep at night suddenly vomit, can also be accompanied by anorexia, nausea, diarrhea and other symptoms. Light generally take general treatment, such as bed rest, light diet, fasting if necessary, drink more water; general treatment after no relief, it is recommended under the guidance of a doctor oral or intravenous rehydration treatment, severe vomiting can be injected omeprazole gastric protection, usually without anti-infective treatment; 4, other: intussusception, intestinal obstruction, intestinal torsion, cranial trauma, intracranial occupancy, acute pancreatitis and many other diseases can also appear such symptoms It is recommended to seek medical attention in a timely manner to clarify the cause of the disease and then treat it.