Constipation can cause blood in the stool. Constipated patients need to use more force during defecation, which can lead to a continuous increase in pressure in the abdominal cavity, resulting in a break in the local blood vessels of the internal hemorrhoids, causing blood in the stool. Most constipated patients will have dry stools, and the dry stools will squeeze the nucleus of the internal hemorrhoids during the process of discharge from the anus, causing them to bleed. Constipated patients have dry stools, which are coarse and hard, and the process of discharging the anal canal may also cause the skin of the anal canal to crack, leading to anal fissures, and causing blood in the stool symptoms. Patients with constipation should eat more vegetables and fruits, drink more water to keep bowel movements smooth, and if necessary, they need to take oral laxative and laxative medications to relieve constipation symptoms.