In the case of organophosphate poisoning, which antidote should be administered first?

In cases of organophosphate poisoning, the administration of atropine is crucial because it works as an anticholinergic agent. Organophosphates are known to inhibit the enzyme acetylcholinesterase, leading to an accumulation of acetylcholine at the synaptic cleft. This excess acetylcholine causes overstimulation of the muscarinic and nicotinic receptors, resulting in symptoms such as bronchoconstriction, excessive salivation, lacrimation, urination, diarrhea, gastrointestinal distress, and potentially fatal respiratory failure.

Atropine acts by blocking the effects of acetylcholine on the muscarinic receptors, thereby alleviating the deadly muscarinic symptoms associated with organophosphate toxicity, such as bronchoconstriction and secretions. Administering atropine promptly is essential to counteract these life-threatening symptoms.

Other antidotes listed, such as N-acetylcysteine, sodium nitrite, and deferoxamine, are used for different types of poisoning or conditions and are not indicated for organophosphate toxicity. N-acetylcysteine is primarily used in acetaminophen overdose, sodium nitrite is used in cyanide poisoning, and deferoxamine is indicated for iron overload conditions.