Iron poisoning

From Infogalactic: the planetary knowledge core
Jump to: navigation, search

Iron poisoning is an iron overload caused by a large excess of iron intake and usually refers to an acute overload rather than a gradual one. The term has been primarily associated with young children[1] who consumed large quantities of iron supplement pills, which resemble sweets and are widely used, including by pregnant women—see overnutrition (approximately 3 grams is lethal for a 2 year old).[2] Targeted packaging restrictions in the US for supplement containers with over 250 mg elemental iron have existed since 1978, and recommendations for unit packaging have reduced the several iron poisoning fatalities per year to almost zero since 1998.[3][4] No known cases of iron poisoning have been identified that are associated with iron mining.

Nature of iron

<templatestyles src="Module:Hatnote/styles.css"></templatestyles>

In nature, iron is usually found in its oxidized form, iron (III) oxide, which is insoluble. Ferrous iron is soluble and its toxicity varies, largely with the integrity of the gastrointestinal lining. Iron supplements are typically used to treat anemia. Modalities include: diet, parasite control,[5] vitamin A, riboflavin (B2),[6] vitamin C (for absorption), folate(B9), vitamin B12 and multivitamin-multimineral supplements,[7] with or without iron; potentially avoiding the use of iron only supplements.[8]

Toxic dosage

The amount of iron ingested may give a clue to potential toxicity. The therapeutic dose for iron deficiency anemia is 3–6 mg/kg/day. Toxic effects begin to occur at doses above 10–20 mg/kg of elemental iron. Ingestions of more than 50 mg/kg of elemental iron are associated with severe toxicity.[9]

  • A 325-mg tablet of ferrous sulfate has 65 mg (20%) of elemental iron
  • A 325-mg tablet of ferrous gluconate has 39 mg (12%) of elemental iron
  • A 325-mg tablet of ferrous fumarate has 107.25 mg (33%) of elemental iron
  • 200 mg ferrous sulfate, dried, has 65 mg (33%) of elemental iron

In terms of blood values, iron levels above 350–500 µg/dL are considered toxic, and levels over 1000 µg/dL indicate severe iron poisoning.[10]

Signs and symptoms

The first indication of iron poisoning by ingestion is a stomach pain, as iron is corrosive to the lining of the gastrointestinal tract including the stomach. Nausea and vomiting are also common symptoms and bloody vomiting may occur. The pain then abates for 24 hours as the iron passes deeper into the body resulting in metabolic acidosis, which in turn damages internal organs, particularly the brain and the liver. Iron poisoning can cause hypovolemic shock due to iron's potent ability to dilate the blood vessels.[citation needed] Death may occur from liver failure.[citation needed]

If intake of iron is during a prolonged period of time, symptoms are likely similar to other causes of iron overload.

Treatment

Later stage treatment consists of cleaning the iron from the blood, using a chelating agent such as deferoxamine. If this fails then dialysis is the next step.

Footnotes and references

  1. Lua error in package.lua at line 80: module 'strict' not found.
  2. Lua error in package.lua at line 80: module 'strict' not found.
  3. Lua error in package.lua at line 80: module 'strict' not found.
  4. Lua error in package.lua at line 80: module 'strict' not found.
  5. Lua error in package.lua at line 80: module 'strict' not found.
  6. Lua error in package.lua at line 80: module 'strict' not found.
  7. Lua error in package.lua at line 80: module 'strict' not found.
  8. Lua error in package.lua at line 80: module 'strict' not found.
  9. Lua error in package.lua at line 80: module 'strict' not found.
  10. Lua error in package.lua at line 80: module 'strict' not found. citing: Gale Encyclopedia of Medicine. Copyright 2008

External links

  • Lua error in package.lua at line 80: module 'strict' not found.
  • Lua error in package.lua at line 80: module 'strict' not found.
  • Lua error in package.lua at line 80: module 'strict' not found. on merckmanuals]