Acute iron poisoning

Mechanism of Action An antidote that binds with iron to form complex. Therapeutic Effect Promotes urine excretion of acute iron poisoning. 

When injected, it forms a stable water-soluble iron complex (ferrioxamine) that prevents the iron from entering into further chemical reactions and is readily excreted in the urine giving the urine a characteristic reddish colour. Some of it is also excreted in the faeces via the bile. It can also chelate aluminium and thus is useful in aluminium overload. It is primarily a chelator used in acute iron poisoning and chronic iron overload as in thalassemia patients needing multiple transfusions. 

It is an orally active iron chelator. It is useful in acute iron poisoning, iron overload in cirrhosis, transfusion siderosis in thalassemia patients. Adverse effects are anorexia, vomiting, altered taste, joint pain and neutropenia. 

Deferoxamine (see also Chapters 58 and 59) Chelates excess iron Reduces the toxicity associated with acute or chronic iron overload Treatment of acute iron poisoning and for inherited or acquired hemochromatosis that is not adequately treated by phlebotomy Preferred route of administration is IM or SC Toxicity Rapid IV administration may cause hypotension acute respiratory distress has been observed with long infusions neurotoxicity and increased susceptibility to certain infections has occurred with longterm use... 

Sudden excessive uptake of soluble iron salts, especially by young children, can lead to acute iron poisoning, characterised by the highly corrosive action of iron... 

Dose. In acute iron poisoning 5 g of desferrioxamine mesylate by mouth, with 2 g intramuscularly, and up to 15 mg/kg/hour by intravenous infusion. 

Treatment of acute iron poisoning is urgent and immediate efforts must be made to chelate iron in the blood and in the stomach and intestine. Raw egg and milk help to bind iron until a chelating agent is available. 

Desferrioxamine has been shown to be effective in the therapy of acute iron poisoning and in the treatment and perhaps in the diagnosis of diseases associated with chronic iron accumulation. A topical formulation is available for ocular siderosis. 

Tenenbein M, Kowalski S, Sienko A, Bowden DH, Adamson lY. Pulmonary toxic effects of continuous desferrioxamine administration in acute iron poisoning. Lancet 1992 339(8795) 699-701. 

Helson L, Helson C, Braverman S, Deb G, Donfrancesco A. Desferrioxamine in acute iron poisoning. Lancet 1992 339(8809) 1602-3. 

Howland MA (1996) Risks of parenteral deferoxamine for acute iron poisoning. Journal of Toxicology Clinical Toxicology 34(5) 491 97. 

Greater than normal concentrations of serum iron occur in iron loading disorders such as hemochromatosis, in patients with aplastic anemia, in acute iron poisoning in children, and after oral ingestion of iron medication or parenteral iron administration or acute hepatitis. For example, one 0.3-g tablet of ferrous sulfate ingested by an adult may raise the serum iron concentration by 300 to 500 U.g/dL (50 to 90)imol/L). 

For ferric iron, the A assoc of deferoxamine is about 10 °, while the Tassoc for Ca " " is about 10. Iron in hemopro-teins is not affected by this agent, while the ferric iron of ferritin and hemosiderin is chelated in preference to that found in transferrin. Such selectivity makes the compound useful in treatment of iron storage problems and acute iron poisoning. 

The toxicity of acute iron poisoning includes local effects on the gastrointestinal mucosa and systemic effects induced by excessive iron in the body. Iron is irritating to the gastric and duodenal mucosa, which may result in hemorrhage and occasional perforations. Once... 

FIGURE 10-7. Pathophysiologyof acute iron poisoning. Events indicated by dashed lies are not observed consistently in all serious poisonings. (ARDS, adult respiratory distress syndrome.)... 

Acute iron poisoning can produce death in children and adults. An analysis by the Consumer Products Safety Commission concluded that iron poisoning remains a significant public health threat to young children based on injury andmortality data from 1980 through 1996. The 2003 AAPCC-TESS report documented 32,991 nonfatal and 4 fatal cases, respectively, of iron poisoning, with 81% of the exposures in children younger than 6 years of age. In most cases (90%), multiple vitamins with iron were the source of iron. ... 

Chyka PA, Butler AY. Assessment of acute iron poisoning by laboratory and clinical observations. Am J Emerg Med 1993 11 99-103. 

Chyka PA, Butler AY, Holley JE. Serum iron concentrations and symptoms of acute iron poisoning in children. Pharmacother 1996 16 1053-1058. 

Berkovitch M, Livne A, Lushkov G, et al. The efficacy of oral deferiprone in acute iron poisoning. Am J Emerg Med 2000 18 36-40. 

Chelation therapy is also used to treat iron overload. Acute iron poisoning, such as that resulting from accidental ingestion of FeS04 tablets, results in corrosion of the gastrointestinal tract. Chronic iron poisoning, or hemochromatosis, arises... 

Serum iron determinations arc of limited routine value, being of most assistance in the diagnosis of iron overload and acute iron poisoning. 

Acute iron poisoning is treated by chelating the iron in the stomach and in the plasma with desferrioxamine (Fig. 4). The chelated iron is excreted in the urine as a deep orange-coloured complex. This should not be confused with myoglobinuria. 

Acute iron poisoning often causes severe gastrointestinal damage due to direct corrosive ef-... 

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