Diarrhea generally refers to diarrhea, drinking coffee will be diarrhea may be fasting coffee, drink spoiled coffee, drink too cold or too much coffee, irritable bowel syndrome and other reasons. 1. Drinking coffee on an empty stomach: when drinking coffee on an empty stomach, the caffeine in the coffee will stimulate the gastric mucosa, which can easily damage the gastric mucosa and induce diarrhea. 2. Drinking spoiled coffee: If you drink spoiled coffee, the bacteria in the coffee will stimulate the mucous membrane of the gastrointestinal tract and induce acute gastroenteritis. Patients will experience abdominal pain, diarrhea, nausea and vomiting. 3. Drinking too cold or too much coffee: If you drink coffee that has been frozen in the refrigerator for a long time or drink too much coffee at one time, it will easily stimulate the gastrointestinal tract and accelerate gastrointestinal peristalsis, which will also cause the symptoms of diarrhea. 4. Irritable bowel syndrome: the cause of irritable bowel syndrome is not clear, and it is considered to be related to visceral hypersensitivity, abnormal gastrointestinal tract dynamics and other reasons. Patients will have diarrhea, abdominal pain and other manifestations, so patients with irritable bowel syndrome will have diarrhea when drinking coffee. When drinking coffee diarrhea is more serious, it is necessary to consult a doctor in time, and the doctor will choose appropriate measures to treat the cause. Normally, you should avoid drinking spoiled or too cold coffee, and should not drink coffee on an empty stomach.