Toxidrome
Formal Definition
A constellation of signs and symptoms that characterize exposure to a particular class of toxic substance, enabling clinical identification of the likely agent class even before laboratory confirmation; the five classic toxidromes are cholinergic, anticholinergic, opioid, sympathomimetic, and sedative-hypnotic.
How It's Used on the Ward
"What toxidrome are we looking at?" — the pattern-recognition approach in toxicology that narrows the differential before the tox screen comes back.
Example
""Altered patient found outside a nightclub: tachycardia 148, hyperthermia 40.2, hypertension, dilated pupils, diaphoresis, and agitation — sympathomimetic toxidrome consistent with cocaine or amphetamines. Supportive care with benzos, cooling measures, avoid beta-blockers.""
Clinical Context
Classic toxidromes: 1) Cholinergic (SLUDGE/DUMBELS — organophosphates, nerve agents): miosis, bradycardia, bronchospasm, hypersalivation, lacrimation, vomiting, diarrhea, urination. Antidote: atropine + pralidoxime. 2) Anticholinergic (antihistamines, TCA, Jimson weed): "dry as a bone, blind as a bat, red as a beet, hot as a hare, mad as a hatter" — mydriasis, tachycardia, urinary retention, confusion. 3) Opioid: miosis, bradypnea, depressed LOC. Antidote: naloxone. 4) Sympathomimetic (cocaine, amphetamines, ephedrine): mydriasis, tachycardia, hypertension, hyperthermia, diaphoresis. 5) Sedative-hypnotic (benzos, barbiturates, alcohol): CNS depression without miosis (vs opioids).