Blood in your Stool: Causes, Colours and When to Worry

A patient’s story

Ellis, 51, noticed streaks of blood on the toilet paper after using the bathroom. He felt well otherwise and assumed it was haemorrhoids. When the bleeding persisted, he sought medical advice. Investigations showed a treatable bowel condition that had been silently progressing. Early assessment made all the difference.

 

Seeing blood in your poo is alarming, but it should never be ignored.

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What does blood in your poo mean?

Blood in your stool, also known as rectal bleeding, indicates bleeding somewhere in the digestive tract. In many cases, the cause is minor. In others, it can signal a more serious gastrointestinal condition.

 

Rarely, it may be associated with bowel cancer, which is why assessment is important even when symptoms are mild.

Symptoms that may occur alongside blood in poo

You may also experience:

  • Abdominal pain or cramping

  • Bloating

  • Diarrhoea or constipation

  • Nausea or vomiting

  • Fatigue or dizziness

When should you seek urgent medical care?

Seek urgent medical attention if blood in your poo is accompanied by:

  • Large volumes of bleeding

  • Sudden bloody diarrhoea

  • Fever

  • Severe abdominal pain

  • Lightheadedness or weakness

  • Rapid or shallow breathing

What does blood in poo look like?

Blood may appear in different ways:

  • Blood on toilet paper

  • Red streaks on stool

  • Pink or red toilet water

  • Bloody diarrhoea

  • Black, tarry stool

The colour of the blood often helps identify where the bleeding is coming from.

What the colour of blood tells us

Bright red blood

Usually comes from the lower bowel or rectum.

Common causes include:

  • Haemorrhoids

  • Anal fissures

  • Diverticular disease

  • Inflammatory bowel disease

  • Infection or severe gastroenteritis

  • Medication effects

  • Bowel cancer

Bright red bleeding is also common during pregnancy and postpartum due to haemorrhoids or fissures.

Dark red or maroon blood

Suggests bleeding higher in the colon or small intestine, and occasionally the stomach.

Possible causes include:

  • Diverticular disease

  • Ulcers

  • Bleeding within the bowel

  • Bowel cancer (less common)

Black, tarry stool

Indicates bleeding from the upper digestive tract, such as:

  • Oesophagus

  • Stomach

  • Duodenum

Common causes include:

  • Stomach ulcers

  • Severe gastritis

  • Upper GI bleeding

Iron supplements and dark foods can also darken stool, but this should still be discussed with a doctor.

Occult or hidden blood

Sometimes blood is not visible and is detected only by stool testing.

Possible causes include:

  • Polyps

  • Ulcers

  • Inflammatory bowel disease

  • Diverticular disease

  • Bowel cancer

🧪
Read more
Understanding the Faecal Occult Blood Test
Learn what the test shows, why it matters, and what your results mean

Polyps and bowel cancer

Blood in poo is rarely caused by cancer, but awareness matters.

Symptoms that may raise concern:

  • Unexplained weight loss

  • Persistent fatigue

  • Change in bowel habits

  • Abdominal pain

  • Feeling an ongoing urge to open your bowels

How we diagnose the cause

Diagnosis depends on symptoms and risk factors. Tests may include:

  • Stool tests

  • Blood tests

  • Digital rectal examination

  • Abdominal imaging

  • Endoscopy, such as colonoscopy or sigmoidoscopy

Treatment options

Treatment depends on the cause and may include:

  • Lifestyle and dietary changes

  • Medication

  • Endoscopic treatment to stop bleeding

  • Surgery, if required

Minor causes such as haemorrhoids or fissures often respond well to conservative management. More complex conditions require specialist care.

Expert assessment brings reassurance

At LSDC Clinic, we provide prompt, expert assessment of rectal bleeding to identify the cause and guide appropriate treatment. Early evaluation offers reassurance and, when needed, timely intervention.

Book a consultation with LSDC Healthcare today.

FAQ's

Is blood in poo always serious?

No, but it should always be checked, especially if persistent or unexplained.

Can haemorrhoids cause bleeding?

Yes. They are a common cause of bright red blood, but diagnosis should be confirmed.

Can diet cause red stool?

Certain foods, such as beetroot, can colour stool, but true bleeding must be ruled out.

Should I have a colonoscopy?

If bleeding persists, or if there are risk factors or additional symptoms, a colonoscopy may be recommended.

When should I see a specialist?

Any ongoing bleeding, uncertainty, or associated symptoms should prompt specialist review.

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