Toxicology & Overdose
Toxicology looks intimidating but reduces to five toxidromes. Recognize the pattern, treat the airway and hemodynamics, give the antidote if you carry one, and transport.
EMT · AEMT · Paramedic
The five toxidromes at a glance
Every overdose scenario on the NREMT maps to one of these patterns — recognize it, then work the airway and antidote.
- Opioid — pinpoint pupils, respiratory depression, decreased LOC (naloxone)
- Sympathomimetic — dilated pupils, tachy, hypertensive, diaphoretic, agitated (benzos)
- Cholinergic (SLUDGE) — salivation, lacrimation, urination, defecation, GI cramping, emesis (atropine + pralidoxime)
- Anticholinergic — 'hot, dry, red, mad' — hyperthermic, dry, flushed, altered (supportive care)
- TCA overdose — wide QRS, hypotension, seizure (sodium bicarb)
Prehospital antidotes worth knowing
Naloxone (opioid), glucagon (beta-blocker/calcium-channel-blocker), calcium (CCB, hyperkalemia), sodium bicarbonate (TCA, severe acidosis), oxygen (CO), atropine + pralidoxime (organophosphate).
Scene safety first
Any overdose scene with unknown substances, needles, or self-harm potential is a scene-safety scenario before it's a medical scenario. Law enforcement, PPE, and decon come before assessment.
Frequently asked
- What's the priority in any overdose?
- Airway and breathing. Most overdose deaths are respiratory. Ventilate, then decide about antidotes.
- Do I induce vomiting?
- No. Ipecac is no longer recommended. Activated charcoal is provider-dependent and only for specific ingestions within one hour.
Test yourself
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