What is the antidote for Iron Toxicity?

Bihar CHO - 2021

Pharmacology

Easy

Appeared in: Bihar CHO - 2021

Explanation

Deferoxamine is the specific chelating agent used as an antidote for moderate to severe iron poisoning.
It works by binding to free ferric iron (Fe³⁺) in the plasma, forming a stable, water-soluble complex called ferrioxamine.
This ferrioxamine complex is then excreted by the kidneys, which characteristically turns the urine a reddish-orange ('vin rosé') color, indicating that iron is being removed from the body.
It is indicated when serum iron levels are very high (e.g., greater than 500 μg/dL) or when the patient shows signs of systemic toxicity like shock or severe acidosis.

Option B: Glucagon is not used for iron toxicity. Its primary role as an antidote is to counteract the effects of beta-blocker and calcium channel blocker overdose by increasing cyclic AMP, which improves heart contractility and rate.
Option C: Famotidine is an H₂-receptor antagonist that reduces stomach acid production. It has no role in chelating iron or treating systemic toxicity from poisoning.
Option D: Protamine sulphate is a specific antagonist for heparin. It binds with heparin to neutralize its anticoagulant effect but has no affinity for iron.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Pharmacology: Antidotes for specific toxicities as background academic context rather than a clinical decision trigger.
Knowing the correct antidote is a critical nursing responsibility in emergency toxicology. Rapid identification and administration can be life-saving.
Nurses must monitor for both the therapeutic effect (e.g., 'vin rosé' urine with deferoxamine) and adverse effects (e.g., hypotension from rapid infusion) of antidote administration.
What if the patient had ingested an unknown substance but presented with bradycardia and hypotension? The nurse's priority would be to stabilize the patient (ABCs), obtain an ECG, and consider antidotes for common cardiotoxic drugs like beta-blockers (Glucagon) or calcium channel blockers, pending further information.

How to Approach the Question

First, identify the core of the question. The question asks for the specific 'antidote' for 'Iron Toxicity'. This is a direct factual recall question from pharmacology.
Scan the options provided: Deferoxamine, Glucagon, Famotidine, Protamine sulphate.
Mentally retrieve or look up the primary use of each drug as an antidote.
Recall that Deferoxamine is a chelating agent specifically used for iron overload.
Confirm the uses of the other drugs to rule them out. Glucagon is for beta-blocker overdose, Famotidine is an acid reducer (not an antidote), and Protamine sulphate is for heparin overdose.
Select Deferoxamine as the only option that correctly matches the poison (iron) with its specific antidote.

Concept Tested & Keywords

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E6 Nelson Textbook of Pediatrics(2024) — Volume 1 p. 759-761