Suddenly not having bowel movement for several days may be related to physiological reasons such as too little diet and exercise, as well as pathological reasons such as irritable bowel syndrome, intestinal tumors, intestinal obstruction, etc. The details are as follows. 1. Physiological reasons: if the amount of food intake in recent days is too little or the amount of exercise is too little, the situation of not having bowel movements for a few days suddenly may occur. 2. Pathologic causes: (1) Functional intestinal diseases: If you suffer from functional intestinal diseases such as irritable bowel syndrome and functional dyspepsia, due to the weakening of gastrointestinal function, the patient may have a sudden failure to relieve bowel movement for several days. (2) Organic intestinal diseases: such as intestinal tumors, colon polyps, intestinal obstruction and other diseases, the patient may also appear suddenly for a few days without bowel movement, and in severe cases, nausea and vomiting, abdominal pain and other symptoms. There are many other reasons for sudden bowel movements, so it is recommended to consult a doctor in time for a clear diagnosis and treatment, so as not to delay the condition.