Ask our doctors: Why am I bleeding from my bum?

What is rectal bleeding?

Dr. Bob: Rectal bleeding is actually a common symptom and occurs when blood is passed from the bottom (or ‘anus'). It's important to sort out, as there are lots of different reasons for rectal bleeding, occasionally including serious causes.

What are the causes of rectal bleeding?

Dr. Mash: These are very broad and tend to range from simple causes such as haemorrhoids (also known as 'piles') or a painful tear around the anal region (called a 'fissure') to more worrying causes like bowel cancer. Chronic inflammation of the colon known as 'colitis' or inflammatory bowel disease can also occur. This is also associated with diarrhoea, urgency to move your bowels and abdominal pain. This usually needs long-term treatment.

Does the amount of redness matter?

Dr. Mash: As a rule, the brighter it is, the more likely it is coming from the end of the large intestine near the anus. Dark red blood often tends to come from higher up in the bowel.

I've heard of piles, what are they and do they cause any other symptoms?

Dr. Mash: These are blood vessels around the anal canal that can become swollen and inflamed often leading to rectal pain and an itchy bum. They are often made worse by constipation or hard stools. The bleeding here is usually bright red. They do not lead to cancer.

When should I be worried?

Dr. Bob: Any prolonged or unexpected bowel symptoms need checking by a doctor. In particular, the older you are, any significant change in your bowel habit or weight loss requires evaluation. Colon (also known as 'bowel' or 'large intestine') cancer is caused by pre-cancerous growths called polyps and can actually be prevented if the polyps are identified and removed early on by undergoing a colonoscopy - this is a camera test up the bottom usually under sedation. Colonoscopy can also identify other causes of rectal bleeding.

Where can I get help?

Dr. Bob: Your GP should usually be your first port of call. They may refer you to a bowel specialist called a gastroenterologist or a colorectal surgeon. Try the very helpful Core Charity website for more information and support.

Dr. Bob and Dr. Mash are our resident doctors. Dr. Bob is a Fellow of the Royal College of Physicians and a consultant. Dr Mash is a member of the Royal College of General Practitioners and a senior GP in London.

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