Decreased Clinical Toxicity and Two-Phase Elimination Kinetics Observed After Intravenous Iron Sucrose Overdose

Area of Science:

• Emergency Medicine
• Clinical Toxicology
• Pharmacology

Background:

• Management of oral iron overdoses is established, but data on intravenous iron sucrose overdoses are limited.
• Deferoxamine is indicated for oral iron overdose with toxicity signs and serum iron ≥ 500 microg/dL.
• Signs of iron sucrose overdose differ from oral iron overdose symptoms.

Observation:

• A patient with a 1000 mg intravenous iron sucrose overdose (5x prescribed dose) presented well-appearing.
• Serum iron concentration was 1799 microg/dL, significantly above the threshold for deferoxamine.
• The patient had normal bicarbonate and anion gap with an unremarkable physical exam.

Findings:

• Despite high serum iron, the patient showed no severe toxicity and received only supportive care.
• Deferoxamine was not administered due to the lack of clinical toxicity signs.
• Serum iron normalized within 14 hours, and the patient was discharged the next day.

Implications:

• Intravenous iron sucrose overdose appears to have lower toxicity than oral iron salt overdose.
• Supportive care alone may be adequate for intravenous iron sucrose overdose, contrasting with oral overdose management.
• The distinct elimination kinetics of iron sucrose may explain the discrepancy between high serum iron levels and low clinical toxicity.