Toxicology Screening Approach: Toxidromes and Antidotes

The NP toxicology screening approach requires systematic recognition of toxidromes combined with targeted antidote administration. The five major toxidromes form the foundation of clinical toxicology assessment: (1) Cholinergic (organophosphates, nerve agents): SLUDGE/BBB with miosis, treated with atropine (titrated to dry secretions) and pralidoxime (reactivates acetylcholinesterase within 24-48 hours before aging occurs). (2) Anticholinergic (diphenhydramine, TCAs, scopolamine): hyperthermia, mydriasis, dry skin/mucosa, tachycardia, delirium, urinary retention — treated with physostigmine for severe cases (must exclude TCA co-ingestion due to seizure/cardiac risk). (3) Sympathomimetic (cocaine, amphetamines): hypertension, tachycardia, hyperthermia, diaphoresis, mydriasis — treated with benzodiazepines for agitation/seizures; avoid beta-blockers in cocaine toxicity (unopposed alpha stimulation). (4) Opioid: respiratory depression, miosis, CNS depression — treated with naloxone titrated to respiratory effort. (5) Serotonin syndrome (SSRIs, MAOIs, tramadol, linezolid combinations): hyperthermia, clonus (especially lower extremity), hyperreflexia, agitation, diaphoresis — treated with cyproheptadine (serotonin antagonist) and benzodiazepines; distinguished from neuroleptic malignant syndrome (NMS) by presence of clonus and hyperreflexia vs lead-pipe rigidity in NMS. Critical diagnostic tools include the anion gap (elevated in MUDPILES: Methanol, Uremia, DKA, Propylene glycol/Paraldehyde, INH/Iron, Lactic acidosis, Ethylene glycol, Salicylates) and...