Gastrointestinal Bleeding & Iron Deficiency
Stabilise bleeding, interpret haemoglobin cautiously and investigate the cause of iron deficiency rather than treating the number alone.
Quick revision ↓ Medical Dictionary
01Recognise significant bleeding
Haematemesis and melaena commonly indicate upper gastrointestinal bleeding, while fresh rectal blood often arises distally but can accompany brisk upper bleeding. Assess circulation, mental state, ongoing loss and comorbidities immediately. A normal initial haemoglobin does not exclude major acute blood loss before redistribution occurs. Obtain help, intravenous access and appropriate blood sampling while arranging resuscitation and urgent specialist review.
02Risk and initial management
Use a validated bleeding-risk pathway alongside clinical judgement. Review anticoagulants, antiplatelets, NSAIDs, alcohol use and liver disease. Blood products and reversal decisions depend on active bleeding, physiology, laboratory findings and thrombotic risks; do not apply a single transfusion threshold mechanically in shock. Endoscopy follows appropriate stabilisation, with urgency determined by the clinical picture and local emergency service.
03Consider the bleeding source
Peptic ulceration, erosive disease, varices and malignancy are important upper sources. Portal-hypertensive bleeding requires a specific urgent pathway that can include vasoactive therapy, antibiotics and endoscopic treatment under specialist care. Bright blood does not automatically identify the level of bleeding. Persistent or recurrent loss may need further endoscopic, radiological or surgical evaluation rather than repeated reassurance from one earlier investigation.
04Interpret iron studies
Microcytosis suggests iron deficiency but also occurs with thalassaemia and some chronic disease patterns. Ferritin reflects iron stores but rises with inflammation, so a normal value may not exclude deficiency in an inflammatory setting. Use the history, full blood count, transferrin saturation and other findings together. Anaemia severity, symptoms and the rate of change determine urgency independently of the cell size.
05Find and address the cause
Iron replacement should accompany investigation of an appropriate underlying cause such as menstrual loss, gastrointestinal bleeding, malabsorption or dietary insufficiency. Adult men and postmenopausal women with unexplained iron deficiency often need gastrointestinal evaluation. Review response and tolerability rather than assuming a prescription resolves the problem. Explain warning symptoms and track whether the haemoglobin and iron stores recover through planned follow-up.
High-Yield Revision
- Assess physiology before interpreting a single haemoglobin.
- Ferritin can be misleadingly normal during inflammation.
- Replace iron and investigate why it was lost.
Common Pitfalls
- Do not assume fresh rectal blood excludes a brisk upper source.
- Do not label every microcytic anaemia as iron deficiency without assessment.
References & Further Reading
Read the relevant guideline sections alongside these original clinical teaching cases. Local pathways, available services and individual patient factors determine care.
Reference review: 27 September 2026. Consult current local protocols for prescribing, procedures and escalation.