If you want to have a bowel movement after eating, it may be caused by irritable bowel syndrome, ulcerative colitis, acute gastroenteritis and other diseases. 1. Irritable bowel syndrome: mostly belongs to the functional lesions, there is no organic lesions, can be manifested as frequent diarrhea, diarrhea after meals, abdominal pain and other phenomena. You can use probiotics, such as chlordiazepoxide to regulate the microecology of the gastrointestinal tract, pay attention to emotional adjustment, and use psychotropic drugs under the guidance of a doctor to assist in the treatment if necessary. 2. Ulcerative colitis: due to inflammation stimulation leads to gastrointestinal peristalsis increase, gastrointestinal peristalsis increase after eating is prone to want to defecate, eat more defecation phenomenon, you can through the mesalazine and other drugs treatment. 3. Acute gastroenteritis: mostly due to bacterial infections caused by the phenomenon, mostly related to unclean diet, but after eating can appear abdominal pain, diarrhea, nausea and vomiting and other symptoms, can be treated with drugs such as levofloxacin. There are other reasons for wanting to have a bowel movement after eating, the above drugs need to be applied under the advice of a doctor, and timely consultation is recommended.