Naloxone

General

• Type: Opioid antagonists, antidote
• Dosage Forms:
• Common Trade Names: Narcan

Adult Dosing

Opioid toxicity

• Bolus (May repeat q3min up to max dose 10mg)
  • Apneic or near-apneic - 2mg IV
  • Opioid-naive with minimal respiratory depression - 0.4mg IV
  • Opioid-dependent with minimal respiratory depression - 0.05mg IV
• Infusion
  • Only give if the patient responded to the bolus and required repeat administration
  • Step 1: Determine the "wake-up dose" or bolus required to wake the pt
  • Step 2: Give 2/3 of the "wake-up dose" per hr; mix in 1L D5W
• Intranasal
  • Pre-mixed nasal spray: 3,4, or 8 mg (1 spray) in one nostril. May repeat q 2-3 minutes if no response
  • IV solution: 2 mg (1 mg each nostril using atomizer)

Pediatric Dosing

• Full reversal (overdose or intoxication)
  • IV/IO: 0.1 mg/kg (max 2 mg). Repeat every 2 to 3 minutes as needed
• Titrated correction of respiratory depression from therapeutic opioid
  • IV/IM/SUBQ: 0.005 to 0.01mg/kg IV every 2 to 3 minutes as needed to desired degree of reversal

Special Populations

• Pregnancy Rating: C
• Lactation: insufficient data
• Renal Dosing: No dose adjustment
• Hepatic Dosing: No dose adjustment

Contraindications

• Allergy to class/drug

Adverse Reactions

• Opioid withdrawal
• Non-cardiogenic pulmonary edema
• Serious complications are rare

Pharmacology

• Metabolism: hepatic
• Excretion: renal
• Mechanism of Action: opioid antagonist (competes for mu receptor binding sites, displacing opioid)
• Onset of action - 1-2min
• Duration of action - 20-90min (may be less than that of the ingested opioid)
• For this reason many hospital algorithms call for ~3 hours of ED observation prior to discharge
• Some small studies have called for decreasing this time frame to 1 hour but there are often adverse events in a significant proportion of these patients (one study showed that 15% of patients had adverse events such as need for supplemental oxygen after attempting discharge at 1 hour).

Indications by Condition

The following table is automatically generated from disease/condition pages across WikEM.

Indication	Dose	Context	Route	Population
Body packing	2-5mg IV initially, repeat 2mg q5min until responsive; then continuous infusion at total response dose/hr	Opioid packet rupture	IV	Adult
Clonidine toxicity	0.4-2 mg IV, may repeat up to 10 mg	CNS/respiratory depression reversal	IV	Adult
Opioid toxicity	2 mg IV (apneic/near-apneic); or 0.4 mg IV (opioid-naïve, mild-mod); or 0.04-0.05 mg IV (opioid-dependent); repeat q2-5min PRN	Opioid reversal (IV/IM/IO)	IV/IM/IO	Adult
Opioid toxicity	4 mg intranasal (may repeat q2-3min)	Opioid reversal (intranasal)	IN	Adult
Opioid toxicity	0.1 mg/kg IV/IM/IO (max 2 mg); or 0.1 mg/kg IN via nasal atomizer	Opioid reversal (pediatric)	IV/IM/IO/IN	Pediatric
Opioid toxicity	Continuous infusion: 2/3 of effective bolus dose per hour	Naloxone drip for recurrent/prolonged toxicity	IV drip	Adult
Valproic acid toxicity	0.4-2 mg, may repeat	Reversal of CNS depression	IV	Adult

See Also

• Opioid toxicity
• Opioid withdrawal