- 0.4 mg/1 ml vials (IV, IM, subcutaneous)

- 2 and 4 mg/spray (intranasal spray)

Executive Summary

(October 24, 2023)

Naloxone is an opioid receptor antagonist extensively used in prehospital settings and EDs to reverse respiratory depression and coma in opioid-intoxicated patients (12, 15). 

Adult dose for opioid overdose

Adult dose

Adult dose for opioid overdose

Pediatric dose

Pediatric dose for opioid overdose in non-opioid-dependent patients (6, 8, 12)


The comatose patient

Opioid toxicity

Mechanism of action


Naloxone pharmacology of IV administration (12, 26).

*TTPE: time-to-peak effect



Adverse effects

Iatrogenic withdrawal management

Pregnancy and lactation

Pregnancy risk classification

Use with caution. Inducing opioid withdrawal in opioid-tolerant mothers will likely induce withdrawal symptoms in the fetus, and should be avoided. This also may occur in newborns. It is worth considering that naloxone has an increased elimination time in newborns of 2 to 3 times longer than adults (12). 

Lactation (20)

Naloxone is considered a low risk drug for the nursing mother and infant. 


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