Toxicity of Iron
1- Acute Iron Toxicity:
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It is seen almost exclusively in young children who have accidentally ingested iron tablets.
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Oral iron preparations should therefore always be stored in “childproof” containers and kept out of reach of children.
Large amounts of oral iron cause:
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Necrotizing gastroenteritis, with vomiting, abdominal pain and bloody diarrhea followed by shock, lethargy, and dyspnea.
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Subsequently, improvement is often noted, but this may be followed by severe metabolic acidosis, coma, and death. Treatment
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Gastric aspiration should be performed, followed by lavage within 1 hour with phosphate or carbonate solutions to form insoluble iron salts.
Desferoxamine (Desferal), a potent iron chelating compound:
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5 gm in 100 ml water should then be instilled into the stomach to bind any remaining free iron in the gut. It is not absorbed from GIT.
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Deferoxamine 1-2 gm should also be given systemically by intermittent IMI or by continuous IV infusion of 15 mg/Kg/hour to bind iron that has already been absorbed and to promote its excretion in urine and feces.
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Appropriate supportive or symptomatic therapy for gastrointestinal bleeding, metabolic acidosis, and shock must also be provided.
2- Chronic Iron Toxicity:
- Most commonly occurs in patients with haemochromatosis which is an inherited disorder characterized by:
- excessive iron absorption
- in patient who receive many red cell transfusions over a long period of time. It results in iron deposition in the heart, liver, pancreas and other organs.