Some mucus in the stool is perfectly natural, as mucus acts as a lubricant in the body, states Healthgrades. However, a great deal of mucus in the stool or mucus that is accompanied by symptoms such as blood, pain or diarrhea can indicate inflammation, bowel obstruction or cancer.
Certain medical conditions of the anus or rectum can also cause mucus in the stool, explains Healthgrades. Rectal ulcers, along with anal fissures and anal fistulas can cause mucus that looks bloody in some cases. People who experience mucus in the stool that is accompanied by a high fever or blood should call 911 or seek immediate medical attention.