Drinking beer the next day diarrhea may have to do with drinking too much alcohol, chronic enteritis, irritable bowel syndrome and other factors. 1. Drinking too much alcohol: beer contains a lot of dietary fiber, alcohol and water. After drinking a lot of beer, the alcohol in the beer will stimulate the intestinal mucosa, make the intestinal peristalsis accelerate, and the patient will have diarrhea symptoms the next day. 2. Chronic enteritis: patients with ulcerative colitis or bacterial enteritis, the intestinal mucosa will be in a state of congestion, edema and erosion for a long time. After drinking a lot of beer, alcohol stimulates the intestinal mucosa, which increases the inflammatory exudate of the intestinal mucosa and accelerates intestinal peristalsis, resulting in diarrhea symptoms on the second day. 3. Irritable bowel syndrome: due to various reasons such as intestinal flora imbalance or staying up late, tiredness, mental stress, etc., resulting in irritable bowel syndrome and increased intestinal sensitivity. Coupled with the fact that patients drink beer at the same time will eat some greasy food and stimulating food, alcohol and food on the gastrointestinal tract caused by double stimulation, will accelerate the gastrointestinal tract peristalsis, so that the next day the symptoms of diarrhea. If you have diarrhea the next day after drinking beer, it is recommended that you go to the hospital in time to identify the cause of the disease and standardize the treatment, so as not to threaten your health.