The lack of bowel movements for several days after diarrhea is related to factors such as irritable bowel syndrome and the absence of food residues in the intestine. Irritable bowel syndrome has a variety of manifestations, the common ones being constipation and diarrhea, and some people are classified as alternating constipation and diarrhea. Patients with irritable bowel syndrome with alternating constipation and diarrhea often experience episodes of constipation after diarrhea, and therefore do not have a bowel movement for several days after diarrhea. During diarrhea, the contents of the intestines are rapidly expelled because of hyperactive bowel movements. After the diarrhea improves, no food residue is present because the intestinal contents have been completely eliminated. During diarrhea, some people have a low dietary intake due to the impact of the disease on their diet, so there is no food residue in the intestine. The stool in the rectum needs to be stored to a certain dosage before a defecation reaction occurs, and when the dosage of stool is insufficient, the stimulation of the rectum is weak, so there is no defecation reaction.