If you notice blood when you open your bowels, don’t ignore it, but equally, try not to panic as it can have many causes, many of them harmless. 

It could be something relatively minor and easy to treat, such as haemorrhoids or an anal fissure. But, blood in your poo is also one of the possible symptoms of bowel cancer and, if this is the case, early diagnosis is critical to catch it before it can spread to other parts of the body. 

When should you seek help?

Really there is no time too early to seek help when it comes to a health concern.

But broadly speaking, if you have had blood in your poo for more than three weeks, it’s important to see your doctor even if you feel a bit embarrassed. The chances are it is nothing serious but, if it is, you want to give yourself the best chance of successful treatment.

Here are some of the possible causes of rectal bleeding:

Haemorrhoids: Also known as piles, these are swollen veins near your anus that can cause pain or itching and may bleed. More than half of us will have haemorrhoids at some point and they can generally be easily treated with creams or surgery.


Anal Fissure: Fissures – cuts or splits – around your bottom can be painful but are not dangerous. They may be caused by constipation or straining and will normally go away by themselves with some simple dietary changes and avoiding dehydration. In some cases they may need surgical repair. 


Inflammatory Bowel Disease: This is the umbrella term for Crohn’s Disease and Ulcerative Colitis, which are chronic conditions caused by inflammation in the intestine. Both conditions can lead to blood in the poo. Unfortunately, they cannot be cured and are normally managed via medication and, on occasions, surgery.

Related post: IBD – What’s it like to have it?


Gastroenteritis: We’ve all experienced the discomfort of a stomach bug, which can cause diarrhoea, pain and vomiting. Blood can sometimes occur as a result of frequently wiping your bottom, which may cause splits and discomfort. 


Peptic ulcer: Peptic ulcers form on the lining of the stomach or small intestine. They may bleed which can produce black, tarry poo. They are linked to bacterial infection and certain types of medication such as steroids.


Bowel cancer: Bloody stools is one of the signs of bowel cancer (also called colorectal cancer) and this can be a cause for concern. Other symptoms are a change in bowel habits (diarrhoea or constipation), tiredness, unexplained weight loss, abdominal pain or a lump, pain around the bottom. Bowel cancer is the 4th most common cancer in the UK but, if diagnosed early, the chances of recovery are good. 

What to look for

You may notice blood streaks of blood on the toilet paper when you go for a poo, or on the poo itself or in the water of the toilet bowl. You might have very dark, smelly poo or bloody diarrhoea. 

What to do

Make an appointment as soon as possible if your poo is black or dark red or if you have bloody diarrhoea. Go to Accident and Emergency if there is a lot of bleeding or you see blood clots.

For other rectal bleeding, see your doctor if the symptoms have persisted for three weeks or more, or sooner to put your mind at ease.

Prompt, accurate diagnosis of bowel conditions in London

Dr Jamie Murphy will perform various diagnostic tests to determine the cause of your symptoms.

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Contact us for more information if you are concerned about your health and would like to see a specialist bowel doctor.

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