Why administer a DuoDote autoinjector after exposure to sarin gas?

• A. The medications stop the action of acetylcholinesterase.
• B. The medications help to counteract the effects on his nervous system.
• C. The medications stop the action of phosgene.
• D. The medications help to remove cyanide from his circulatory system.

Answer: (B)

Sarin inhibits acetylcholinesterase, causing a surge of acetylcholine that overstimulates the nervous system and produces dangerous cholinergic symptoms. DuoDote contains two drugs: atropine and pralidoxime. Atropine blocks muscarinic receptors, reducing secretions, bronchial constriction, bradycardia, and other muscarinic effects. Pralidoxime reactivates acetylcholinesterase that has been inactivated by the nerve agent, helping restore normal breakdown of acetylcholine at the neuromuscular junction and nicotinic receptors. Together, they counteract the widespread nervous system effects caused by sarin exposure.

The other options aren’t correct because the treatment doesn’t stop the action of acetylcholinesterase itself, it aims to restore its function; it isn’t about stopping a different agent like phosgene, nor does it remove cyanide from the blood.