Rectal bleeding

Start with urgency

Bleeding that will not stop or a large amount, especially with severe dizziness or fainting, needs urgent care. New black stool, dark blood or bloody diarrhoea needs prompt assessment according to the situation. Do not wait to finish a questionnaire or collect images if unwell. Use local emergency services wherever you are. Iron or dark foods can sometimes change stool colour, but their presence does not establish that black stool is harmless. Report medicines and changes so the cause can be assessed.

Clinical background: NHS — Rectal bleeding

How can you describe bleeding clearly?

Record onset, frequency, and whether blood is on paper, on the stool surface, mixed through stool or separate. Mention clots or mucus and whether bleeding is increasing, improving or recurring. You do not need an exact volume in millilitres; a clear observation is better than a guessed number. Include pain, a change in bowel habits or unintended weight loss if present. If you are unsure whether the source is the anus, say so rather than building the history around an uncertain assumption.

Colour is a description, not a diagnosis

Similar-looking red bleeding can occur in different conditions. Pain during bowel movements, prolapse, diarrhoea with mucus or a sustained change in bowel habits adds context, but does not replace examination when needed. Diagnosing by colour can lead you to overlook a new change because of old haemorrhoids. Explain what is different this time, when the last assessment occurred and the result of any previous endoscopy. Bring the report if available rather than relying only on the recollection that it was normal.

What can examination and endoscopy add?

Assessment may start with history, examination and selected tests, followed by further investigation depending on findings. An anal examination and endoscopy do not always answer the same question: a local source may be seen while other features still warrant bowel assessment. Ask why each test is needed and what happens if it does not explain the bleeding. Previous endoscopy and biopsy reports can clarify what was assessed and what still needs follow-up.

Clinical background: NIDDK — Diagnosis of Gastrointestinal Bleeding

Blood thinners do not remove the need to assess the source

List blood-thinning medicines, aspirin, pain medicines and supplements, together with their prescribed purpose if known. Do not independently stop prescribed treatment because of bleeding; other risks may need balancing. Contact the team for appropriate instructions. If several services are involved, record their advice to avoid conflicting directions. Managing a medicine safely and identifying the bleeding source are separate questions. Answering one does not mean the other has been resolved.

After a reassuring assessment, when should you return?

Ask for a plan for persistent or recurrent bleeding: what should improve, when to return and which change needs earlier contact. Record the actual response to treatment. A reassuring assessment is not a promise that every future episode has the same cause. Equally, another small spot does not automatically mean serious disease. Compare symptoms with what was examined and the agreed advice. A brief record of dates, findings and medicines helps a later assessment start from useful information.