Special Populations & Toxicology

N-acetylcysteine (NAC) — a glutathione precursor/substitute that detoxifies the reactive metabolite NAPQI. Most effective within 8 hours; dosing guided by the Rumack-Matthew nomogram (4-hour level).

Naloxone — a competitive mu-opioid antagonist that reverses respiratory depression. Short half-life means re-sedation is possible (esp. with long-acting opioids like methadone or extended-release), so repeat dosing or infusion may be needed.

Flumazenil — a competitive GABA-A benzodiazepine-site antagonist. Use cautiously: it can precipitate seizures/withdrawal in benzodiazepine-dependent patients or in mixed overdoses with proconvulsants (e.g., TCAs).

"Hot as a hare, blind as a bat, dry as a bone, red as a beet, mad as a hatter" — hyperthermia, mydriasis, dry skin/mucosa, flushing, urinary retention, delirium. Antidote: physostigmine (a centrally acting cholinesterase inhibitor).

Muscarinic excess — SLUDGE/DUMBELS: Salivation, Lacrimation, Urination, Defecation, GI distress, Emesis; plus bronchorrhea/bradycardia. Bronchorrhea/bronchospasm are the killers.

Atropine (antagonizes muscarinic effects, dried secretions — titrate to clear lungs) PLUS pralidoxime (2-PAM, reactivates acetylcholinesterase before "aging"). Atropine does not address nicotinic/muscle weakness — pralidoxime does.