Approach to Toxidromes


At Morning Report at WCH we discussed a classic case of a toxic ingestion. Below is an overview of an approach to toxidromes, which are clinical signs and symptoms associated with classes of toxins. Remember that in any acute intoxication, you should diagnose and treat at the same time.

Approach to Acute Intoxication/Toxidrome

    • Airway:
      • Intubate if not protecting airway e.g GCS <8, unless rapidly reversible (e.g., hypoglycemia or opioid overdose with antidotes).
      • May need to intubate for pooling secretions, vomiting, hypoxia
    • Breathing:
      • Monitor O2 sat, ETCO2, provide oxygen and respiratory support as needed
    • Circulation:
      • Get a 12 Lead ECG (e.g., to look for QTc prolongation or wide QRS) and put patient on a cardiac monitor
      • Frequent BP checks
      • Vascular access
      • IV fluids/pressor support for shock
    • Disability and dextrose:
      • Primary neurologic survey including GCS, pupils, movement of extremities).
      • Always check glucose! 
    • Elimination/exposures:
      • Remove clothing, transdermal patches, external contaminants, measure temperature and treat as necessary. Search for clues to overdose and/or medical history.
  • MOIF (Monitors, Oxygen, IV access, Foley)
  • Get STAT bloodwork (see below), a 12 lead ECG (looking for example for QTc prolongation or wide QRS)
  • Consider neuroimaging
  • DONT= Universal antidotes (dextrose- 1 amp D50W, oxygen, naloxone 0.4mg IV and increase doses, thiamine 100mg IV)
  • Focused history and physical exam
  • Call Poison Control!


Below are some helpful charts to remember how to distinguish between different toxidromes.

Image result for classic toxidromesImage result for nms vs serotonin syndrome


  • Accucheck! (Don’t ever forget glucose!)
  • CBC, lytes/extended lytes, BUN/Cr, liver enzymes, INR/PTT
  • Serum osmolality
    • AG = Na – Cl – Bicarb
    • Osmolality = 2xNa + Glucose + BUN
    • Osmolar gap = SOsm- CalcOsm
  • Lactate, ABG
  • Urinalysis
  • Beta-HCG
  • Troponin, CK
  • Tox screen: Serum (ASA, toxic alcohols, tylenol etc) and urine
    • Consider specific drug levels


  • Always remember your ABCs – stabilize the patient!
  • All patients should also receive provide supportive care.
  • Think about the pharmacokinetics of any ingestion:
    • Absorption: Consider activated charcoal
    • In recent ingestion (2-4 hours, but possibly longer if delayed gastric emptying), unless contraindicated (low GCS or aspiration risk, ileus, bowel obstruction) or will not be effective (e.g., toxic alcohol, heavy metals)
    • Metabolism: Antidote or competitive inhibitors
      • Specific treatments vary depending on the toxidrome/ingestion in question. E.g., digibind for digoxin overdose, NAC for tylenol overdose, atropine for cholinergic overdose
    • Elimination: Consider  alkalinization of the blood or urine (e.g., ASA overdose), saline diuresis, hemodialysis or ECLS (See

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