Rectal Bleeding

Rectal bleeding (bleeding from the bottom) is common, experienced by around 10% of adults every year. It is usually seen as a small amount of bright red blood on the toilet paper, but sometimes there is a larger volume which can be alarming. It can have several causes:

  • The most common cause, haemorrhoids (piles), swollen blood vessels around the anus.
  • A small tear in the skin at the anus (anal fissure)
  • A small tunnel or connection between the anal canal and the anus (anal fistula).
  • Angiodysplasia, abnormal blood vessels in the gut. This bleeding is usually painless.
  • Diverticulis, or small bulges in the bowel wall which can rupture, causing usually painless but often copious blood loss.
  • Bowel cancer or bowel polyp. Sometimes bleeding is the only sign of bowel cancer, but other symptoms can be anaemia or changed bowel habit (diarrhoea or constipation). Your GP will advise whether you should be tested, and will refer you if necessary, usually for a colonoscopyflexible sigmoidoscopy or CT Colonography.
  • Inflammatory bowel disease. If stool has become very loose and frequent and especially if you have gripes or colicky tummy pain too it could be a sign of an inflammatory bowel diseases such as Ulcerative Colitis or Crohn’s Disease. You should see your GP as soon as possible if you have these symptoms.
  • Anticoagulant drugs such as warfarin can sometimes cause bleeding.
  • Trauma to the anus

Some patients experience ‘wet wind’ or losing a little blood or mucus when wind is passed. This should always be investigated urgently, as it can be a sign of serious disease.

Dark or sticky blood in the stool might also be a sign of serious disease and should be treated as an emergency.


Your GP or surgeon might perform a rectal examination, where a gloved finger is inserted into the anus to check for problems, or may carry out a rigid sigmoidoscopy . He or she may refer you for further tests, such as colonoscopy or flexible sigmoidoscopy, depending on your symptoms.

Never ignore rectal bleeding. Although it is usually not serious, it can be a sign of bowel cancer and early diagnosis gives the best chance of recovery.

Please be advised that the information on this website is not a substitute for professional medical advice, diagnosis or treatment