Rectal Bleeding

If you have rectal bleeding, this guide can help you to identify some of the causes that are most likely to explain your symptoms. It also may help to explain the recommendations your doctor might make for your evaluation and treatment. This guide is not intended to replace a face-to-face evaluation with your doctor.

Rectal bleeding refers to dark or red blood that you see with a bowel movement or at times between bowel movements. You may notice the blood in the toilet or on your toilet tissue.

You should always contact your doctor if you notice rectal bleeding.

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It will help us to know how you learned about your bleeding. Some people see blood in the stool and others are told by a doctor that a chemical test on the stool was positive for blood (called guiac or hemocult).

I saw blood.

My stool tested positive for blood with a chemical test.

A chemical test has detected blood in your stool. This suggests that you have been in the care of a doctor, either to have symptoms evaluated or to have a routine examination.

Blood that leaks gradually into the stool can be invisible to your eye, but it can amount to a significant amount of blood loss over time. Your doctor may check (or may have checked) a blood test to find out whether you have anemia (a low red blood cell count) due to your blood loss. Your iron supplies in the body can also be measured with a blood test.

If you have stomach pain or nausea, your doctor may recommend endoscopy (EGD), a camera evaluation of your upper digestive tract. This tests looks for an ulcer. If you do not have upper abdominal pain or nausea, your doctors may recommend a colonoscopy test to check for polyps or other causes of bleeding in the colon. Some people need both tests to find the source of bleeding.

Some causes of invisible blood in the stool include:

Peptic ulcer

It is possible for peptic ulcers to bleed heavily, but they can also deposit small amounts of blood in the stool.

Colon polyps

Colon polyps are bulges of intestine tissue that dangle or protrude into the hollow of the colon. They sometimes bleed. Polyps need to be removed because they may form cancers if they are left within the intestine.

Colorectal cancer

Colorectal cancer is the second most common cause of death from cancer in the United States. It is preventable, if colon polyps are discovered and removed. Colorectal cancer can be cured by surgery if it is identified at an early stage. Cancer is most common in people who are over age 50.

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