Blood in Your Stool: What It Means and What to Do About It

Medically Reviewed By Saurabh Sethi, M.D., MPH

Blood in the stool is an abnormal, potentially serious condition in which blood is mixed in with a bowel movement or feces. The blood can arise from anywhere along the digestive tract, from the mouth to the anus. Bloody stool is often a sign of gastrointestinal (GI) bleeding due to injury or disease. Bright red or maroon-colored blood that passes with stool may be referred to as “hematochezia,” while “melena” describes black, tarry, and smelly stools.

Read on to learn more about potential causes and treatments for blood in your stool.

What are the causes of blood in your stool?

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Jamie Grill Atlas/Stocksy United

Blood in the stool can indicate a relatively mild condition like hemorrhoids or constipation, or it can be due to a serious condition such as esophageal varices or colon cancer.

Upper GI tract causes of blood in stool

The upper GI tract includes the esophagus, stomach, and duodenum. The duodenum is the upper part of the small intestine.

Potential causes of bloody stool related to the upper GI tract include:

Lower GI tract causes of blood in stool

The lower GI tract runs from the lower part of the small intestine to the anus. Causes of bloody stool related to the lower GI tract may include:

Other causes of blood in stool

Bloody stool can also be a side effect of radiation therapy or certain medications, like low dose aspirin taken long term.

Serious or life threatening causes of blood in stool

In some cases, bleeding may accompany a serious or life threatening condition, including:

What can blood in your stool look like?

Blood in the stool can appear in various forms. Small amounts of bright red blood may be mixed inside the stool or show up on toilet paper after wiping the anus.

Visible blood clots can also be present. Blood in the stool is sometimes accompanied by open bleeding from the rectum.

Black, tarry stools may indicate that the blood is coming from the upper GI tract. As blood travels through the GI tract, secretions convert hemoglobin into an acid called hematin, which darkens the color of the blood.

Red or maroon-colored stools often originate from bleeding in the lower GI tract.

What other symptoms might occur with blood in your stool?

Depending on the underlying condition, blood in your stool may occur with other symptoms such as:

How do doctors diagnose the cause of blood in your stool?

To diagnose the underlying cause of bloody stool, doctors may begin by performing a physical examination and taking a detailed medical history. Determining whether hematochezia or melena is occurring is important to narrow down the part of the GI tract that may be involved.

If doctors suspect bleeding in the upper GI tract, they may perform an endoscopy to determine the cause and potentially treat the condition at the same time.

For lighter-colored bloody stool, a digital rectal exam may help doctors determine whether there are masses or hemorrhoids. A colonoscopy can allow doctors to visually examine the colon and rectum and potentially treat any bleeding.

In some cases, a diagnosis of the cause of blood in the stool can be delayed or missed because tiny amounts of blood may not be noticeable for long periods. Blood in the stool that is not immediately visible due to the small quantity is called fecal occult blood.

If doctors suspect fecal occult bleeding based on other symptoms, they may order a fecal occult blood test. This test involves assessing 1–3 stool samples to check for blood.

What are the treatments for blood in your stool?

In the short term, treatment for bloody stool may involve IV fluids or blood transfusions, depending on the severity of the bleeding.

Depending on the underlying cause, doctors may prescribe certain medications to promote healing in the GI tract. Proton pump inhibitors (PPIs) may encourage healing by reducing damage from stomach acid, and a drug called “octreotide” may benefit people experiencing bleeding from esophageal varices.

Doctors may be able to treat bleeding in the lower GI tract during a colonoscopy. In some cases where medications or other therapeutic methods are insufficient, surgery may be necessary.

What are the potential complications of blood in your stool?

Over time, blood in the stool can lead to serious complications, including:

When should you worry about blood in your stool?

A healthcare professional should evaluate any blood in the stool.

In some cases, bloody stool may occur with other symptoms that might indicate a serious or life threatening condition. Seek immediate medical care if you’re experiencing any of these serious symptoms:

Other frequently asked questions

Here are a few other common questions about blood in your stool. Saurabh Sethi, M.D., M.P.H., has reviewed the answers.

Can food make your stool bloody?

Certain foods, like beets or foods that contain red food coloring, may cause your stool to appear bloody but will not make you bleed. Contact your doctor if you have blood in your stool and have not eaten any red foods.

How much blood is too much in stool?

You should contact your doctor if you notice any blood in your stool. While it may result from a temporary minor condition, like constipation, it may also indicate a more serious condition.

How long do hemorrhoids bleed?

The length of time that hemorrhoids bleed can change from person to person. However, if your symptoms have not resolved after 1 week, contact your doctor.

Summary

Blood in your stool can result from various conditions. If you’re experiencing bloody stool, contact your doctor. They can help you identify the cause and decide on a treatment plan.

Medical Reviewer: Saurabh Sethi, M.D., MPH
Last Review Date: 2022 Oct 27
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
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