5 Leading Causes of Blood In Stool, and Treatment Pathways

By: Lambros Michailidis, M.D.

You’ve likely noticed remnants of what you’ve eaten before hitting the handle on the toilet bowl – a bit of corn, an undigested nut, the pinkish hue of a beet salad. But if you think you saw something that looks like blood in your stool, do not flush the image away.

Gastrointestinal bleeding, or GIB, is highly common, requiring more hospitalizations than any other GI diagnosis in the U.S., according to the National Library of Medicine. Still, blood in stool (word of the day: hematochezia) can be potentially fatal if ignored, depending on its underlying source.

Colon cancer, for example, often causes blood in stool (and March is ).

There are less serious sources of GIB as well. Risk factors include being older, male, or a smoker. Alcohol and medication can also bring on GIB.

This is why it happens.

How Blood in Stool Can Occur

A healthy stool gets its color mainly from what you eat and bile, a greenish digestive fluid that turns brown while traveling through the digestive tract.

If GIB occurs, that brown can turn bright red to black, depending on where the bleeding starts. Because your GI tract is long, stretching from your esophagus (food pipe) to your anus, the causes of gastrointestinal bleeding are divided into two categories:

Upper GIB – This bleeding originates in the esophagus, stomach, or first part of the small intestine, called the duodenum. It can produce blood in stool as well as bloody vomit that looks like coffee grounds. Upper GIB accounts for nearly 40% of GIB-related hospital admissions, the National Library of Medicine reports.

Lower GIB – Lower GI bleeding occurs anywhere south of the duodenum, meaning the large intestine (colon), rectum, and anus. Here, the blood in stool is typically brighter. Lower GIB is not as common as upper GIB, but is more prevalent among men than women.

Underlying Causes of Blood In Stool

Gastrointestinal bleeding symptoms vary depending on where in the upper and lower GI they occur.

Among the causes of each upper GIB:

Gastroesophageal reflux disease (GERD) – GERD occurs when food and acids in the stomach back up into the esophagus, often because the muscular band at the top of the stomach loosens. When reflux becomes frequent, the acids can inflame and irritate the esophagus and make it bleed. An estimated 8% of people with chronic GERD have blood in stool.

• Symptoms – Frequent burping, bad breath, chronic sore throat, pain and/or difficulty when swallowing, and nausea/vomiting. A yellow stool from food moving too fast through the intestinal tract.
• Treatment options – The first approach to GERD treatment typically involves dietary changes, weight loss, and avoiding nicotine and alcohol. If symptoms persist, the doctor might recommend medication or surgery.

Peptic ulcers – Though not as common as GERD, open sores in the digestive tract, called peptic ulcers, are the leading culprit behind upper GI bleeding. They can develop in your stomach (gastric ulcers) or the upper part of the lower intestine (duodenal ulcers).

• Symptoms – Abdominal pain, bloating, heartburn, belching, nausea/vomiting, and anemia. A dark red, maroon, or black stool.
• Treatment options – Acid-reducing medications along with antibiotics can treat the underlying cause of the ulcers. The bleeding can also be cauterized, or medication directly injected, through an upper endoscopy, in which the doctor threads a tiny viewing camera and instruments through the esophagus to the stomach.

Conditions that can cause lower GIB include:

Inflammatory bowel disease (IBD) – In some people, the immune system attacks intestinal cells, causing persistent inflammation that could lead to bleeding. IBD occurs in the colon, called colitis, or deep in the intestines, called Crohn’s disease.

• Symptoms – An urgent and more frequent need to go to the bathroom, diarrhea, abdominal pain, skin rash, and joint pain. Blood in stool reflects the location of the bleeding – bright red if in the colon (colitis) or darker if higher up the digestive tract.
• Treatment options – IBD care is based on symptoms and severity but often includes changes in diet and reducing stress, as well as anti-inflammatory or immunosuppressant medications.

Hemorrhoids – Hemorrhoids are like varicose veins in the posterior; the vessels have swollen and bulge through the anus, often due to pushing or pressure.

• Symptoms – Anal discomfort and itching, lumps from blood clotting, and veins pushing through the anus (prolapse). Blood on toilet paper and in the stool that is bright red.
• Treatment options – Changes in diet and hydration, as well as stool softeners and creams, can ease symptoms. If the hemorrhoids persist, the doctor can cut off their blood supply (banding) or remove the clots, among other minimally invasive procedures.

Gastrointestinal cancers – If small masses of cells or polyps begin to grow abnormally in the esophagus, stomach, or colon, they can develop into cancer. Colon cancer forms more slowly than the others, typically taking five to 10 years to develop.

• Symptoms – Colon or stomach cancer can trigger abdominal pain, gas and cramps, fatigue, and changes in bowel movements. Signs of esophageal cancer include difficulty swallowing and heartburn. All cancers produce blood in stool; the color intensity depends on the cancer location.
• Treatment options– Approaches for care focus on the organs affected by the cancer. Treatment may require radiation, chemotherapy, and surgery to remove the ulcer.

You can stop the (GI) bleeding

Next time you use the bathroom, take a moment to look at your stool before you flush, especially if you experience any of the above symptoms. It might not be pretty, but it is a pretty good way to prevent a GI condition from worsening.

Cincinnati GI physicians and staff are ready to answer all of your GI questions. Click here to request an appointment at one of our seven locations.