Passing small amounts of bright red blood from the anus or rectum (back passage) is common. It may occur on its own or with an associated change in bowel habit and is most often due to a minor local condition such as haemorrhoids ('piles') or a tear in the delicate skin lining the back passage (called an anal fissure). Bleeding can sometimes be the result of inflammation in the rectum (proctitis) or a polyp (benign growth) in the bowel, but rectal bleeding is also an important symptom of bowel cancer. Bowel cancer can occur at any age but is rare below the age of 40.
Most people with persistent or recurrent rectal bleeding should be investigated for the cause Gastroenterologists regularly investigate people with this symptom, usually by colonoscopy.
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