Abdominal discomfort, nausea and vomiting may be caused by acute gastroenteritis, chronic gastritis, peptic ulcer and pyloric obstruction. 1. Acute gastroenteritis: may be eating unhygienic food triggered acute gastrointestinal inflammation, manifested as abdominal discomfort, nausea, vomiting symptoms. 2. Chronic gastritis: such as superficial gastritis, atrophic gastritis, etc., due to the damage and erosion of gastric mucosa and increased secretion of gastric acid, which leads to the above symptoms. 3. Peptic ulcer: the protective barrier of gastric mucosa is damaged, and there is ulcer surface, gastric acid will stimulate the ulcer surface lesion, resulting in abdominal discomfort, nausea, vomiting and other symptoms. 4. Pyloric obstruction: stomach contents cannot be smoothly discharged from the pylorus into the duodenum, resulting in increased abdominal pressure, causing stomach discomfort, nausea, vomiting and other discomforts. It is recommended to consult a doctor in time for the above symptoms, identify the cause of the disease under the guidance of a professional physician, and treat it as soon as possible.