Learn About the Causes of Mucus in the Stool and if This Sign Indicates the Need for Medical Attention

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Mucus exists naturally throughout the digestive system, serving as a protective layer and lubricant. In helps food move smoothly through the esophagus, stomach, small intestine and large intestine (which includes the colon and rectum). It also protects the body from its own digestive acids as well as any harmful bacteria or viruses which may have been ingested with the food. Many different problems in the digestive track can cause the body to produce more mucus than normal, with the excess ending up in the stool.

The following list of medical conditions covers all causes of mucus in stool.

Intestinal Infection

An infection in the intestines by harmful microbes like bacteria, viruses, parasitic worms or protozoa can cause dysentery and inflammation. The symptoms of an infection can vary from case to case, but usually involve diarrhea with blood and mucus, abdominal pain, and a fever. Most people will see their symptoms clear up within one week as their body fights off the infection.


Hemorrhoids occur when normal veins carrying blood become enlarged either inside the anal canal (internal) or next to the anus opening (external). Internal hemorrhoids can cause mucus to come out with fecal matter. Hemorrhoids arise when veins in the anus are put under increased pressure, stretching them out. This pressure can come from straining during bowel movements, constipation, diarrhea, or even pregnancy. Bleeding from the anus, especially during bowel movements, is the most common symptom of hemorrhoids. Other symptoms include discomfort, pain, or itching.

Anal Fissures

An anal fissure is simply a tear in the anal canal. Like hemorrhoids, anal fissures may be caused by excessive strain during bowel movements as well as constipation and diarrhea. Infants are more prone to anal fissures. Someone with an anal fissure usually experiences pain and some bleeding during their bowel movements. Like a cut, the fissure will heal naturally with time and usually doesn’t require professional treatment.

Irritable Bowel Syndrome

Irritable bowel syndrome, or IBS, is a condition defined by its uncomfortable symptoms including cramping and pain in the abdomen, constipation, diarrhea, and bloating. It is usually diagnosed when patients report these symptoms along with a change in the frequency and appearance of their bowel movements. Scientists do not know what causes irritable bowel syndrome. For some people, eating particular foods or experiencing high levels of stress can be enough to trigger the disorder. Treatment to reduce IBS symptoms usually involves diet changes. Eating more fiber, drinking more water, and avoiding large meals often help people with IBS.

Inflammatory Bowel Disease

Crohn’s disease and ulcerative colitis are two related disorders which are referred to together under the title of inflammatory bowel disease, or IBD. Both are chronic diseases which cause inflammation of the intestines. Both cycle between flaring up and going into remission throughout someone’s life, although ulcerative colitis mostly affects those under the age of 30. Scientists are unsure as to the exact causes of these diseases, but suspect the body may be having an unusual immune response to healthy normal bacteria found in the intestines.

Ulcerative colitis causes ulcers and inflammation in the lower intestinal tract. Crohn’s disease can cause inflammation anywhere in the digestive tract, from the mouth to anus. With both conditions, symptoms include abdominal pain and diarrhea many times a day, often with blood and mucus. Treatment for both conditions usually involves anti-diarrheal and anti-inflammatory medicines prescribed by a doctor.


Mayo Clinic: Mucus in stool: Is it a concern?

UK National Health Service: Dysentery - Symptoms

Mayo Clinic: Anal fissure

National Institute of Health: Irritable Bowel Syndrome

WebMD: Inflammatory Bowel Disease Health Center