Pharm

Quetiapine Overdose

search

Quetiapine Overdose, Seroquel Overdose, Quetiapine Toxicity, Quetiapine Poisoning

  • See Also
  • Pharmacokinetics
  1. See Quetiapine (for pharmacokinetics and mechanisms)
  • Signs
  1. Tachycardia
    1. Related to Quetiapine as a weak Muscarinic Antagonist (M1)
  2. Hypotension
    1. Related to Quetiapine as a potent alpha-1 Adrenergic Receptor antagonist
  3. Somnolent with Miosis
    1. Mimics Opioid Overdose
    2. Sedation related to weak antagonist activity at Dopamine (D2), muscarinic (M1) and Serotonin (5HT-1A)
  • Labs
  1. See Unknown Ingestion
  2. Urine drugs screen may show false positive Tricyclic Antidepressant in Quetiapine Overdose
  1. Tachycardia
  2. QTc Prolongation
    1. Quetiapine in Overdose may impact delayed rectifier current
  3. QRS Widening
    1. Quetiapine in Overdose may block fast Sodium channels
  • Management
  1. See Unknown Ingestion (consider coingestions)
  2. Decontamination
    1. Consider Activated Charcoal in alert patient if presentation <1-2 hours (especially extended release form)
  3. ABC Management
    1. Apnea is rare with Quetiapine Overdose, but Endotracheal Intubation as needed
  4. Hypotension Management
    1. Intravenous Fluids
    2. Vasopressors as needed (e.g. Norepinephrine)
    3. Consider Intralipid in refractory shock
  5. Neuroleptic Malignant Syndrome (rare)
    1. See Neuroleptic Malignant Syndrome
    2. Benzodiazepines
    3. Initiate Active Cooling of Patient
  6. Disposition
    1. Asymptomatic patient and normal Electrocardiogram at 6 hours requires no further telemetry monitoring
  • References
  1. Otter and Tomaszewski (2018) Crit Dec Emerg Med 32(8): 32