UMEM Educational Pearls

Category: Pharmacology & Therapeutics

Title: Naloxone: Low Dose, Quick Reassessment

Keywords: naloxone, opioid (PubMed Search)

Posted: 4/11/2024 by Ashley Martinelli (Updated: 7/14/2024)
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Naloxone is given frequently in the emergency department to improve the respiratory rate in patients with suspected or known opioid ingestion.  In order to minimize the risk of severe opioid withdrawal (nausea, vomiting, diarrhea, anxiety, piloerection, sweating, agitation, etc.), consider diluting naloxone and administering small aliquots of 0.04-0.08mg at a time.  This requires IV access and a patient with a present, but low respiratory rate.

Dilution instructions:


  • 10 mL vial of 0.9% sodium chloride
  • 1 vial of 0.4 mg/mL naloxone
  • 1 empty 10 mL syringe/needle


  1. Withdraw 9 mL of 0.9% sodium chloride into an empty syringe. 
  2. Add 1 mL of naloxone 0.4 mg/mL
  3. Label syringe as: Naloxone 0.04 mg/mL

Administer 1 -2 mL (0.04 – 0.08 mg) naloxone every 2 minutes and assess response.

Don't forget to prescribe/give naloxone upon discharge from the emergency department.