Common Causes of Rectal Bleeding

Seeing blood when you’re using the bathroom can come as a frightening surprise but it’s not always an indication of a serious health problem.  Regardless, it’s still recommended that you schedule an appointment with a gastroenterologist, like the ones at Manhattan Gastroenterology, for a checkup as soon as possible.  Don’t worry quite yet though, there are many reasons you might see blood in your stool and it’s important to know that plenty of them are not serious or life threatening. Keep reading for more information on some of the most common causes of rectal bleeding.

Anal Fissures

Anal fissures are small tears and cuts that appear in the anal lining that can develop as a result of chronic constipation, straining, or from passing hard stools. Typically, these tears and not serious and will heal on their own within a few weeks, but during that time you may experience mild rectal bleeding. To reduce the chance of developing anal fissures in the future, add more fibrous foods to your diet and increase your water intake, both of which contribute to softer stools and help to prevent constipation.


The most common cause of rectal bleeding is hemorrhoids, which are swollen veins in the rectum or around the anus that can be quite painful. Hemorrhoids develop from a number of different causes including constipation, pregnancy, obesity, heavy lifting and anal intercourse, generally the cause of the hemorrhoids must be identified to properly treat them. Bleeding occurs when the tissue covering these swollen veins is damaged or irritated, most often while passing stool or doing physical labour that causes strain. Medical intervention is often required to begin the healing process once hemorrhoids have formed, and treatments range from non invasive to surgical depending on the location and severity.


Similar to hemorrhoids, Angiodysplasia is a condition where swollen blood vessels can become irritated and release blood into stool which can be bright red or appear black if the blood is arterial. Unlike hemorrhoids these fragile blood vessels are located only the colon and are Irritated by normal internal spasms. Angiodysplasia is generally a result of aging and affects mostly older adults and warrants an immediate visit to the doctor to confirm the cause of bleeding and the amount of blood loss occurring.

Peptic Ulcer

Peptic Ulcers are sores or breaks that form on the inside lining of the stomach or intestines that can cause a painful burning irritation that may improve with eating, though a majority of people with peptic ulcers experience no symptoms at all. Bleeding from an ulcer will often appear black and tarry, but in rare cases it can travel quickly through the body and appear bright red in your stool, if this is the case you are likely experiencing heavy bleeding. It is important to see a doctor right away if you are experiencing either of these types of bleeding, especially if they manifest without any pain, because you may have undiagnosed ulcers which will worsen without medical intervention.

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