Infant vomiting is one of the common symptoms in infancy and can be caused by a variety of reasons and should be treated according to the different causes. Common causes include the following two: (1) Infection: acute gastroenteritis, meningitis, otitis media, urinary tract infection, bacterial or viral hepatitis. (2) Improper feeding: feeding too much milk, too often, inappropriate milk distribution, such as milk concentration is too high, can cause high plasma osmotic pressure, and cause vomiting. (3) Allergic diseases: such as milk protein allergy. (4) Cranial hypertension: subdural edema, hydrocephalus, cerebral edema. (5) Gastroesophageal reflux. (6) Drug intoxication or withdrawal: common in withdrawal syndromes (morphine, heroin, antipsychotics, etc.). (7) Metabolic and endocrine disorders: hypocalcemia, acute renal failure, acute adrenal insufficiency due to congenital adrenocortical hyperplasia, and some rare genetic disorders (galactosemia, amino acid metabolic disorders, fructose intolerance). (2) Surgical diseases leading to spitting up: (1) GI malformations: esophageal atresia, esophagotracheal fistula, esophageal hiatal hernia, congenital hypertrophic pyloric stenosis, gastric torsion, gastric perforation, intestinal atresia, intestinal stenosis, intestinal torsion malformation, intestinal duplication malformation, megacolon, annular pancreas, etc. (2) Gastrointestinal diseases: meconium intestinal obstruction, meconium peritonitis, NEC, intussusception, appendicitis, etc.