FMGE 2009 — Pharmacology

Question 1: Which of the following is NOT used for iron poisoning?

• A. EDTA (Ethylenediaminetetraacetic acid)
• B. Desferrioxamine
• C. Gastric lavage
• D. Penicillamine (Correct Answer)

Explanation: ***Penicillamine*** - **Penicillamine** is a chelating agent indicated for **copper poisoning** (Wilson's disease), **lead poisoning**, and **rheumatoid arthritis**, but has **no role in iron poisoning**. - It works by chelating copper, lead, and other heavy metals, but does not effectively chelate iron. - This is the most clearly incorrect option as it is never indicated for iron toxicity. *EDTA (Ethylenediaminetetraacetic acid)* - **EDTA** is primarily used for **lead poisoning** and hypercalcemia. - While not routinely used for iron poisoning, it can form iron-EDTA complexes, which may paradoxically worsen toxicity. - **CaNa₂EDTA** is avoided in iron poisoning due to potential complications. *Desferrioxamine* - **Desferrioxamine (Deferoxamine)** is the **first-line antidote** for severe iron poisoning. - It is a highly specific iron-chelating agent that binds free iron in the bloodstream and promotes its renal excretion as ferrioxamine. - It reduces iron-mediated oxidative damage to organs (especially liver, heart, and GI tract). *Gastric lavage* - **Gastric lavage** can be used as a decontamination method in acute iron poisoning if performed early (within 1-2 hours of ingestion). - It helps remove unabsorbed iron tablets from the stomach, reducing further systemic absorption. - Whole bowel irrigation with polyethylene glycol is often preferred for iron tablet ingestion.