From the Guidelines
Iron toxicity symptoms include nausea, vomiting, abdominal pain, and diarrhea in the early stages, which typically occur within 6 hours of ingestion, and can progress to severe complications such as liver damage, metabolic acidosis, coagulopathy, and even death, as noted in studies on iron overload and its effects on various organs 1.
Symptoms of Iron Overload or Acute Iron Intoxication
The symptoms of iron overload or acute iron intoxication can be categorized into early and late stages. In the early stages, which typically occur within 6 hours of ingestion, symptoms may include:
- Nausea
- Vomiting
- Abdominal pain
- Diarrhea As toxicity progresses, symptoms may include:
- Lethargy
- Rapid breathing
- Low blood pressure
- Shock Severe cases can lead to:
- Liver damage
- Metabolic acidosis
- Coagulopathy
- Even death Children may experience symptoms at lower doses than adults, with as little as 20 mg/kg of elemental iron potentially causing toxicity 1.
Treatment and Prevention
Treatment involves supportive care, possibly gastric lavage if the ingestion was recent, and in severe cases, chelation therapy with deferoxamine 1. Iron toxicity occurs because excess iron generates free radicals that damage cells, particularly in the liver and heart. The body lacks an efficient mechanism to eliminate excess iron, making prevention crucial. If iron toxicity is suspected, immediate medical attention is necessary as the window for effective intervention is narrow, especially in children.
Monitoring and Management
For patients with chronic iron overload, monitoring serum ferritin levels and associated organ dysfunction (heart, liver, and pancreas) is essential, as noted in the study on myelodysplastic syndromes 1. The goal of treatment is to decrease ferritin levels to less than 1000 mcg/L. Iron chelation therapy, such as deferoxamine or deferasirox, may be considered to decrease iron overload in patients with low or intermediate-1 risk disease who have received or are anticipated to receive greater than 20 red blood cell transfusions 1.
From the FDA Drug Label
OVERDOSAGE Acute Toxicity ... Signs and Symptoms Inadvertent administration of an overdose or inadvertent intravenous bolus administration/rapid intravenous infusion may be associated with hypotension, tachycardia and gastrointestinal disturbances; acute but transient loss of vision, aphasia, agitation, headache, nausea, pallor, CNS depression including coma, bradycardia and acute renal failure have been reported Acute respiratory distress syndrome has been reported following treatment with excessively high intravenous doses of deferoxamine mesylate in patients with acute iron intoxication
The symptoms of iron overload or acute iron intoxication are not directly listed, but symptoms associated with acute iron intoxication and overdose of deferoxamine mesylate include:
- Hypotension
- Tachycardia
- Gastrointestinal disturbances
- Acute loss of vision
- Aphasia
- Agitation
- Headache
- Nausea
- Pallor
- CNS depression including coma
- Bradycardia
- Acute renal failure
- Acute respiratory distress syndrome 2
From the Research
Symptoms of Iron Overload or Acute Iron Intoxication
The symptoms of iron overload or acute iron intoxication can vary in severity and may include:
- Gastrointestinal symptoms such as nausea, vomiting, and abdominal pain 3, 4, 5, 6
- Neurologic signs of toxicity 3
- Severe anion gap metabolic acidosis 3
- Hypotension 4, 6
- Shock 6
- Multi-organ failure 4, 6, 7
- Disseminated intravascular coagulation 6
- High leucocytosis 6
- Liver and renal failure 7
- Metabolic acidosis 7
- Hypoglycemia 7
- Obtundation 7
Severity of Iron Intoxication
The severity of iron intoxication is based on the amount of iron ingested, and symptoms can range from mild gastrointestinal discomfort to multi-organ failure 5. The serum iron level measured at four to six hours after ingestion is a useful laboratory test to determine toxicity 5.
Clinical Presentation
Clinical presentation can vary, and individualized treatment decisions should be based on the patient's clinical presentation and laboratory values 5. In some cases, patients may be minimally symptomatic despite ingesting a toxic dose of iron 5. In other cases, patients may present with delayed symptoms, making diagnosis and treatment more challenging 7.