Physostigmine is used with caution in anticholinergic toxicity because of risks including hypersalivation, AV block, seizures. Which drug's adverse effects limit its use?

Physostigmine is used with caution in anticholinergic toxicity because of risks including hypersalivation, AV block, seizures. Which drug's adverse effects limit its use?

• A. Physostigmine
• B. Atropine
• C. Scopolamine
• D. Neostigmine

Answer: (A)

In anticholinergic toxicity, physostigmine can reverse central and peripheral symptoms by increasing acetylcholine, but it also can unleash excessive cholinergic activity. The biggest limiting factors are its own adverse effects—hypersalivation and other cholinergic secretions, bradycardia that can progress to AV block, and the risk of seizures. These potential life-threatening effects mean physostigmine must be used with careful monitoring and is reserved for selected cases. The other drugs listed don’t limit physostigmine in this context: atropine and scopolamine are anticholinergic agents the antidote is meant to counteract, and neostigmine, which does not cross the blood–brain barrier and would worsen peripheral cholinergic effects, is not used for anticholinergic toxicity.

In anticholinergic toxicity, physostigmine can reverse central and peripheral symptoms by increasing acetylcholine, but it also can unleash excessive cholinergic activity. The biggest limiting factors are its own adverse effects—hypersalivation and other cholinergic secretions, bradycardia that can progress to AV block, and the risk of seizures. These potential life-threatening effects mean physostigmine must be used with careful monitoring and is reserved for selected cases. The other drugs listed don’t limit physostigmine in this context: atropine and scopolamine are anticholinergic agents the antidote is meant to counteract, and neostigmine, which does not cross the blood–brain barrier and would worsen peripheral cholinergic effects, is not used for anticholinergic toxicity.