The more common causes of sudden stomach pain and diarrhea in the middle of the night are acute gastroenteritis and irritable bowel syndrome. It is recommended to pay attention to dietary regimen and take antidiarrheal and antibacterial drugs as prescribed by the doctor, which can usually improve the symptoms of abdominal pain and diarrhea. Common causes and treatments 1, acute gastroenteritis: when patients eat unclean food during the day or dinner, these foods carry E. coli, Salmonella, Staphylococcus aureus and other microorganisms will produce toxins that stimulate the mucosa of the gastrointestinal tract, triggering intestinal cramps. If the defense function of the gastrointestinal tract is weak at this time, the disease may start quickly and manifest as sudden abdominal pain at night with diarrhea symptoms. Some patients with severe disease may also show vomiting and low-grade fever. Oral montelukast can be given, and then promptly go to the hospital to avoid continuous aggravation of symptoms; 2. Irritable bowel syndrome: Patients with irritable bowel syndrome may experience sudden stomach pain and diarrhea in the middle of the night if they are not covered at night, eat a big bucket of ice cream before going to bed or have high mental stress for a long time. It is recommended to relax, pay attention to the routine of life, avoid drinking alcohol, tea and eating a lot of stimulating food before going to bed, pay attention to keeping warm while sleeping and do not let the air conditioner or electric fan blow directly on the abdomen. Special reminder that some patients may not have the above conditions, but sudden stomach pain and diarrhea in the middle of the night, consider going to the local hospital to clarify the cause and treat the symptoms.