Overdose of acetylcholinesterase inhibitors/organophosphates is treated with which initial therapy?

• A. Pralidoxime
• B. Atropine
• C. Diazepam
• D. Glucagon

Answer: (B)

When organophosphate or acetylcholinesterase inhibitor poisoning occurs, acetylcholine floods muscarinic receptors, causing troublesome secretions, bronchospasm, bradycardia, and miosis. The priority in treatment is to rapidly block these muscarinic effects to stabilize breathing and circulation. Atropine acts as a competitive antagonist at muscarinic acetylcholine receptors, quickly reducing airway secretions, broncho-spasm, and bradycardia, thereby improving the patient’s airway and hemodynamics. Pralidoxime can re-activate acetylcholinesterase and helps reverse both muscarinic and nicotinic symptoms, but the immediate lifesaving step is atropine to counteract the dangerous muscarinic effects. Diazepam may be used for seizures, and glucagon has no role in this scenario.