Iron poisoning is a life-threatening toxicological emergency caused by ingestion of excessive elemental iron, most commonly from iron tablets used in treatment of anaemia or prenatal supplementation. It is one of the leading causes of fatal poisoning in children under 6 years because iron tablets resemble sweets.

Unlike many other metals, iron causes direct corrosive gastrointestinal injury and systemic cellular toxicity, resulting in metabolic acidosis, shock, hepatic failure, and death if untreated.

Common preparations involved:

• Ferrous sulfate

• Ferrous fumarate

• Ferrous gluconate

• Prenatal vitamins containing iron

• Multivitamins

• Industrial iron salts

2. Pathophysiology

Iron toxicity occurs in two phases:

A. Local corrosive phase (Gastrointestinal)

Free iron damages mucosal cells → necrosis → bleeding → fluid loss

B. Systemic phase

Absorbed iron overwhelms transferrin binding capacity → free circulating iron causes:

• Mitochondrial poisoning

• Lipid peroxidation

• Cellular death

• Lactic acidosis

• Hepatic necrosis

Cellular Effects

3. Toxic Dose

4. Risk Factors

• Children <6 years (accidental ingestion)

• Pregnant mothers using iron tablets

• Improper storage of medicines

• Intentional overdose (suicide attempt)

• Malnutrition

• Multiple supplement use

5. Clinical Features

Iron poisoning progresses through 5 classical stages

Stage 1: Gastrointestinal Phase (0–6 hours)

• Nausea

• Vomiting

• Abdominal pain

• Diarrhoea

• Grey/black vomitus or stool

• Hematemesis

• GI bleeding

Stage 2: Latent

Phase (6–24 hours)

• Temporary improvement⚠️ Dangerous false recovery — systemic toxicity begins internally

Stage 3: Shock and Metabolic Phase (12–24 hours)

• Hypotension

• Tachycardia

• Metabolic acidosis

• Drowsiness

• Convulsions

• Coma

Stage 4: Hepatic Failure (24–72 hours)

• Jaundice

• Coagulopathy

• Hypoglycaemia

• Liver failure

Stage 5: Late Complications (2–8 weeks)

• Gastric outlet obstruction

• Bowel scarring/stricture

6. Diagnostic Criteria

Suspect iron poisoning if:

• Child ingested tablets

• Vomiting + abdominal pain within 6 hrs

• Black/grey vomitus or stool

• Shock or acidosis unexplained

7. Investigations

Essential

• Serum iron level (4–6 hrs post ingestion)

• Arterial blood gas

• Serum electrolytes

• Blood glucose

Additional

• Full blood count

• Liver function tests

• Coagulation profile

• Renal function tests

• Abdominal X-ray (radio-opaque tablets visible)

Serum Iron Interpretation

8. Management

Treat immediately — do not wait for laboratory confirmation if symptomatic

8.1 Initial

Stabilization (ABCDE)

Airway

• Intubate if altered consciousness

Breathing

• Oxygen

Circulation

• IV fluids for shock

• Treat acidosis

8.2 Decontamination

Gastric lavage

Indicated if large ingestion within 1 hour

Whole bowel irrigation

For multiple tablets seen on X-ray

Activated charcoal does NOT bind iron

8.3 Antidote Therapy —

Deferoxamine

Chelates free iron → forms ferrioxamine → excreted in urine (pink/red “vin-rose urine”)

Indications

• Serum iron >500 µg/dL

• Severe symptoms

• Metabolic acidosis

• Shock

• Altered consciousness

Dosage

IM (moderate poisoning)50 mg/kg deep IM every 12 hours(Max 1 g per dose)

IV (severe poisoning)15 mg/kg/hour infusionMaximum 80 mg/kg/day

Continue until:

• Clinical improvement

• Serum iron <300 µg/dL

8.4 Supportive Care

• Treat seizures (benzodiazepines)

• Correct hypoglycaemia

• Manage liver failure

• ICU monitoring

9. Complications

Early

• Hypovolemic shock

• Metabolic acidosis

• Seizures

Late

• Liver failure

• Gastric scarring

• Intestinal obstruction

10. Prognosis

11. Prevention

Do’s

• Store tablets in locked cabinets

• Use child-resistant containers

• Educate caregivers

Don’ts

• Keep tablets in handbags

• Call medicines sweets

• Transfer pills to envelopes