November 2026

Blood and Mucus in Stool: Causes and Warning Signs

By Your Health Magazine Health Information Team

Faeces with blood and mucus can result from irritation near the anus, inflammation in the rectum or colon, an intestinal infection, inflammatory bowel disease, or another source of gastrointestinal bleeding. A small amount of mucus alone can be normal, but visible blood and mucus together should not be ignored. Contact a healthcare professional promptly, particularly if the symptom recurs or occurs with diarrhea, fever, abdominal pain, weight loss, or a change in bowel habits.

What the Appearance May Tell You

The color and location of the blood may provide clues, although appearance alone cannot identify the cause. The National Institute of Diabetes and Digestive and Kidney Diseases’ guidance on gastrointestinal bleeding notes that bleeding may produce bright red, dark red, or black and tarry stool.

What you notice	What it may suggest
Bright red streaks on stool or toilet paper	Bleeding close to the anus, such as from a hemorrhoid or anal fissure
Blood mixed with mucus or diarrhea	Inflammation or infection affecting the rectum or colon
Dark red or maroon stool	Bleeding farther inside the colon or, occasionally, higher in the digestive tract
Black, sticky, tar-like stool	Possible bleeding from the stomach or upper digestive tract; urgent evaluation is needed

Iron supplements, bismuth-containing medicines, beets, and some food colorings can change stool color. However, do not assume that an unexplained red or black bowel movement is caused by food or medicine when bleeding is possible.

Common Causes of Blood and Mucus in Stool

Hemorrhoids and anal fissures

Hemorrhoids are swollen blood vessels in or around the anus. They commonly cause bright red blood on toilet paper, on the outside of stool, or in the toilet bowl. An anal fissure is a small tear that may develop after constipation, straining, hard stool, or frequent diarrhea. Fissures often cause sharp pain during or after a bowel movement.

These conditions can explain fresh blood, but they do not always explain substantial mucus. Even if hemorrhoids seem likely, persistent or recurrent bleeding should be evaluated rather than self-diagnosed.

Proctitis and other rectal inflammation

Proctitis is inflammation of the rectal lining and is a particularly relevant cause of pooping mucus and blood. It may also cause rectal pain, diarrhea or constipation, urgency, and the feeling that another bowel movement is needed even when the bowel is empty. Causes include inflammatory bowel disease, certain infections, previous pelvic radiation, and some sexually transmitted infections involving the rectum.

Clear or jelly-like discharge without obvious stool may have overlapping causes. Learn more about what clear, jelly-like mucus from the anus may indicate.

Inflammatory bowel disease

Ulcerative colitis and Crohn’s disease cause ongoing inflammation in parts of the digestive tract. Ulcerative colitis commonly causes diarrhea, rectal bleeding, abdominal cramps, urgency, and mucus or pus in the stool, according to the NIDDK overview of ulcerative colitis symptoms. Symptoms may come and go, but repeated episodes of blood in mucus during a bowel movement warrant medical assessment.

Intestinal infections

Bacterial infections such as Salmonella, Shigella, Campylobacter, and certain types of E. coli can cause bloody or mucus-filled diarrhea. Other symptoms may include sudden abdominal cramps, fever, nausea, vomiting, and urgency. Infection may be more likely after unsafe food or water exposure, recent travel, contact with someone who has diarrhea, or recent antibiotic use.

The CDC’s information about food poisoning symptoms advises seeking care for bloody diarrhea, diarrhea lasting more than three days, frequent vomiting, high fever, or dehydration. Avoid taking medicines that slow the bowel, such as loperamide, for bloody diarrhea unless a healthcare professional specifically recommends them.

Other possible causes

Diverticular disease: Pouches in the colon wall can sometimes bleed, while inflammation of the pouches may cause significant abdominal pain and fever.
Colon polyps or colorectal cancer: These can cause visible or hidden blood, persistent bowel changes, unexplained weight loss, fatigue, or a feeling of incomplete emptying. These symptoms often have noncancerous causes, but evaluation is important.
Reduced blood flow to the colon: Ischemic colitis may cause sudden abdominal pain followed by bloody diarrhea and requires urgent medical attention.
Medication-related bleeding: Aspirin, nonsteroidal anti-inflammatory drugs such as ibuprofen or naproxen, and blood-thinning medicines may contribute to gastrointestinal bleeding. Do not stop a prescribed medicine without guidance from the prescriber.

How the Cause Is Diagnosed

A primary care clinician or gastroenterologist will consider the amount and color of blood, how long the problem has lasted, bowel habits, pain, fever, recent travel, food exposures, medications, family history, and previous digestive conditions. Testing may include:

A physical and rectal examination
A complete blood count to look for anemia or significant blood loss
Stool testing for bacteria, parasites, inflammation, or hidden blood
Sigmoidoscopy or colonoscopy to inspect the rectum and colon
Imaging when heavy bleeding, diverticular disease, reduced blood flow, or another complication is suspected

Before an appointment, note when the bleeding started, whether blood is mixed into the stool or only on its surface, the stool color, and any associated pain, diarrhea, fever, urgency, or weight change. A photograph may help document the appearance if you are comfortable taking one. General information about digestive conditions and medical testing is also available through the MedlinePlus health topics directory.

When to Seek Care

Call 911 or go to an emergency department if bleeding is heavy or continuous, you pass large clots, your stool is black and tarry, or you develop fainting, confusion, severe weakness, pale or clammy skin, shortness of breath, a rapid heartbeat, vomiting blood, or severe abdominal pain.

Seek prompt medical evaluation for any blood and mucus stool that recurs or is accompanied by fever, worsening cramps, persistent diarrhea, vomiting, dehydration, unexplained weight loss, fatigue, rectal pain, or a major change in bowel habits. Prompt care is also appropriate for children, pregnant people, older adults, people with weakened immune systems, and anyone taking a blood thinner.

A single small streak after passing a hard stool may come from minor anal irritation, but contact a healthcare professional if it happens again, the source is uncertain, or other symptoms appear. Blood and mucus are symptoms rather than a diagnosis, and the appropriate treatment depends on identifying the underlying cause.