The main causes of stomach pain, diarrhea, nausea and vomiting are acute gastroenteritis, alcohol stimulation and food poisoning. 1. Acute gastroenteritis: it is a syndrome in which acute bacterial and viral infections occur in the gastrointestinal tract, producing a series of intense inflammatory reactions. Because the inflammatory factor stimulates the mucosa of the gastrointestinal tract, the main clinical manifestations of patients include stomach pain, diarrhea, nausea and vomiting and general discomfort. 2. Alcohol stimulation: after drinking alcohol, alcohol enters the body and causes vasoconstriction and reduced blood flow, which can have an adverse effect on brain tissues including the cerebral cortex, leading to cerebral hypoxia, thus causing central nervous system dysfunction. Will make people produce dizziness, nausea, and alcohol will also stimulate the gastric mucosa, triggering stomach pain, diarrhea, vomiting and other symptoms. 3. Food poisoning: If you eat moldy or add a large number of preservatives in the food, may cause food poisoning, the central nervous system and the stomach have a certain stimulation, the patient usually have stomach pain, diarrhea, nausea, want to vomit and other clinical manifestations. Patients with stomach pain, diarrhea, nausea and vomiting should stop eating immediately, and then go to the hospital to receive symptomatic treatment, so as to prevent electrolyte disorders caused by severe diarrhea and vomiting.