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Iron poisoning
Iron poisoning, mainly in children who swallowed prenatal vitamin tablets, is calculated by the dose of elemental iron per kilogram; above 60 mg/kg systemic toxicity with acidosis, shock and liver injury is expected, and treatment is whole bowel irrigation and IV deferoxamine — not activated charcoal.
Why it matters in the exam
The classic question presents a toddler found near a bottle of prenatal vitamins, with vomiting and bloody diarrhoea, and tests the dose calculation: below 20 mg/kg elemental iron — usually no symptoms; 20–60 mg/kg — gastrointestinal symptoms; above 60 mg/kg — severe systemic toxicity. A serum iron level is taken 4–6 hours after ingestion, and a level above 500 µg/dL indicates severe poisoning.
The staged course is also tested: gastrointestinal symptoms in the first hours; a misleading "quiet phase"; then shock and metabolic acidosis; liver injury after two to three days; and gastric outlet stricture after weeks. A patient with no vomiting or diarrhoea in the first six hours is at very low risk of severe poisoning.
Treatment: the tablets are visible on an abdominal X-ray, so the X-ray guides whole bowel irrigation with polyethylene glycol; activated charcoal does not bind iron. IV deferoxamine (15 mg/kg per hour) is given for shock, severe acidosis, altered consciousness, a level above 500 µg/dL or many tablets on X-ray; the urine sometimes turns a "vin rosé" colour. Treatment longer than 24 hours is linked to lung injury.
Key points
- Calculate elemental iron per kilogram: below 20, 20–60, above 60.
- Level after 4–6 hours; above 500 µg/dL — severe poisoning.
- Tablets show on X-ray; bowel irrigation, not charcoal.
- IV deferoxamine 15 mg/kg per hour in severe poisoning.
- No gastrointestinal symptoms after 6 hours — low risk.
Summary table
| Elemental iron dose | Expected picture | Test | Treatment |
|---|---|---|---|
| Below 20 mg/kg | Usually no symptoms | — | Observation at home or in the ED according to circumstances |
| 20–60 mg/kg | Vomiting, diarrhoea, abdominal pain | Iron level at 4–6 hours, abdominal X-ray | Observation, fluids, bowel irrigation according to the X-ray |
| Above 60 mg/kg | Shock, acidosis, liver injury | Blood gas, iron level, liver tests | IV deferoxamine, bowel irrigation, support |
| Level above 500 µg/dL | Severe poisoning | Repeat the level | Deferoxamine 15 mg/kg per hour |
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Sources
- Goldfrank's Toxicologic Emergencies, 11th edition (2019) — Iron
- Tintinalli's Emergency Medicine: A Comprehensive Study Guide, 9th edition (2020) — Iron
- Manoguerra AS et al., Iron ingestion: an evidence-based consensus guideline for out-of-hospital management (Clinical Toxicology), 2005 — Dose thresholds
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.