A patient at an insecticide manufacturing plant has vomiting, diarrhea, breathing difficulties, twitching, and weakness after a splash. What is the preferred treatment to block excessive acetylcholine effects?

• A. Administer atropine
• B. Administer pralidoxime (2-PAM Cl)
• C. Administer diazepam
• D. Administer epinephrine

Answer: (B)

Organophosphate poisoning from insecticide exposure causes a buildup of acetylcholine by inhibiting acetylcholinesterase. The best antidote to block these excessive acetylcholine effects is pralidoxime (2-PAM), which reactivates the inhibited acetylcholinesterase enzyme. Restoring AChE activity allows acetylcholine to be broken down again, addressing both muscarinic symptoms (such as vomiting, diarrhea, and respiratory issues) and nicotinic symptoms (like twitching and weakness). Atropine can relieve muscarinic effects by blocking acetylcholine receptors, but it doesn’t reverse the enzyme inhibition or prevent ongoing acetylcholine accumulation, so it isn’t the sole solution. Diazepam and epinephrine don’t target the underlying mechanism.