What is rectal bleeding?
Rectal bleeding often reveals itself as bright red blood on the
toilet paper—usually after a bowel movement—or by
turning the toilet bowl water red. Rectal bleeding can also present
as extremely dark stool, ranging in color from deep red/maroon to
black, and sometimes appearing tar-like (melena).
The color of the blood can indicate where the bleeding is
occurring:
- Bright red blood usually indicates bleeding low in the colon or
rectum
- Dark red or maroon blood usually indicates bleeding higher in
the colon or the small bowel
- Melena usually indicates bleeding in the stomach, such as
bleeding from ulcers
Not all rectal bleeding is visible to the eye. In some cases,
evidence of rectal bleeding can only be seen through a microscopic
examination of a stool sample or by a test called a Hemoccult®
test which can be done in a doctor’s office.
What causes rectal bleeding?
Although rectal bleeding is common, only about one-third of those
affected seek treatment. Symptoms usually develop quickly, and most
causes are treatable and not serious. In some cases, rectal
bleeding can be a symptom of a serious disease, such as colorectal
cancer. Therefore, all rectal bleeding should be reported to the
primary care physician. He or she can do a rectal examination or
order tests like a colonoscopy to determine the cause of the
bleeding.
Rectal bleeding can be caused by:
- hemorrhoids
- anal fissure
- anal abscess or fistula
- diverticulosis/diverticulitis
- inflammatory bowel disease (IBD)
- ulcers
- large polyps
- colon cancer
What are the symptoms associated with rectal
bleeding?
The symptoms of rectal bleeding may include:
- Rectal pain and/or pressure
- Bright red blood in/on the stool, on underwear, and/or in the
toilet
- Red, maroon, or black stool color
- Stool that has a tar-like appearance
- Confusion
- Feeling lightheaded or dizzy
- Fainting
Overview of common causes of rectal bleeding
What are hemorrhoids, the most common cause of rectal bleeding?
Hemorrhoids are swollen veins in the rectum (internal hemorrhoids)
or the anus (external hemorrhoids). Hemorrhoids, also called piles,
can commonly develop because of chronic constipation or straining
at stools, pregnancy, work strain (heavy lifting, etc.), obesity,
or anal intercourse.
Hemorrhoid treatment includes addressing the underlying causes,
such as treating the constipation or straining habits, or changing
work habits if necessary. Sometimes surgical treatment is necessary
and may include one of the following methods:
- Rubber band ligation: a rubber band placed around the base of
the hemorrhoid cuts off circulation to the bulk of the hemorrhoid
and causes the hemorrhoid to wither away.
- Sclerotherapy: the injection of a chemical solution around the
blood vessel shrinks the hemorrhoid.
- Laser: a precise laser beam is used to burn away small
hemorrhoids.
- Hemorrhoidal arterial ligation: uses a Doppler probe to locate
and tie the blood vessels feeding the hemorrhoid, to shrink
it.
- Procedure for prolapsed hemorrhoids (PPH): puts hemorrhoids
that have come out of the anal canal back in their original
positions.
- Hemorrhoidectomy: surgical removal of the hemorrhoid.