Diarrhea refers to diarrhea, drinking water in the morning diarrhea may be due to the gastrointestinal tract stimulation, acute gastroenteritis, irritable bowel syndrome and other reasons. 1. Stimulation of the gastrointestinal tract: Drinking water in the morning, especially when drinking cold water on an empty stomach, will cause stimulation of the gastrointestinal tract, making the gastrointestinal tract to accelerate peristalsis, leading to the phenomenon of hyperactive colon movement, which may lead to diarrhea symptoms. 2. Acute gastroenteritis: For patients suffering from acute gastroenteritis, there may be diarrhea, bloating, epigastric pain, loss of appetite and other symptoms, and the symptoms of diarrhea can occur at any time. Therefore, some patients may also experience diarrhea when they get up in the morning and drink water. 3. Irritable Bowel Syndrome (IBS): For patients suffering from IBS, symptoms such as abdominal pain, bloating, diarrhea, abdominal discomfort, change in bowel habits, etc. may occur, but there is no abnormality in the examination of other items. If the symptoms of diarrhea occur repeatedly in the morning after drinking water, it is recommended to go to the hospital in time to clarify the causes of diarrhea, and standardized treatment under the guidance of the doctor.