Kids accidentally ingest medicines. In the Peds ED we are rightfully worried about opiates, BP meds, acetaminophen, and diabetes drugs (among many others) but we shouldn’t overlook the potential dangers that come with iron ingestion. Let’s take a look shall we?
Why do humans need iron?
Iron is a part of lots and lots of proteins and enzymes especially hemoglobin, myoglobin, and cytochromes.
What is the normal dose?
For iron deficiency anemia children generally get 4 to 6 mg/kg/day.
How much do normal people have in their body?
Normal serum iron levels generally range from 65 to 175 mcg/dL.
Is it a common severe ingestion?
Less so than in the past as a result of improved packaging
What are the toxicologic effects and toxic dose range?
Iron is a cellular poison and it is also directly corrosive to the GI mucosa. Ingestions of <40 mg/kg generally don’t lead to major toxicity, although mild GI irritation may develop. With peak level >300 mcg/dL Mild symptoms are likely to occur. Peak concentrations > 500 mcg/dL generally cause severe symptoms. Certainly symptoms may not correlate with peak concentration if the patient presents a while after the ingestion.
Would you care to elaborate on the differences between mild, moderate and severe toxicity?
Mild to Moderate
Vomiting and diarrhea may occur within 6 hours of ingestion. if you don’t see this then it is unlikely the patient took a toxic dose. You might not need to get a level according to some toxicologists.
This is where it gets dicey. Again, with levels >500 mcg/dL you can see significant vomiting and diarrhea, lethargy, metabolic acidosis, shock, GI hemorrhage, coma, seizures, hepatotoxicity, and late onset GI strictures. There are 5 phases of iron toxicity.
PHASE I (0.5 to 2 hours) includes vomiting, hematemesis, abdominal pain, diarrhea, hematochezia, lethargy, shock (from GI bleed), acidosis, and coagulopathy. GI tract necrosis occurs from the direct effects of iron.
PHASE II (>2 but <12 hours) apparent recovery
PHASE III (2 to 12 hours after phase I) Profound shock, severe metabolic acidosis, CNS depression, cyanosis, and fever.
PHASE IV (2 to 4 days) Hepatotoxicity perhaps due to direct action of iron on mitochondria. This is when the hepatic profile can be the most helpful. Acute lung injury may also be seen.
PHASE V (days to weeks) GI scarring and strictures.