Dosing & Uses
Dosage Forms & Strengths
injectable solution
- 0.4mg/mL
- 1mg/mL
IM/SC auto-injector
- 0.4mg/0.4mL (2 auto-injectors/package)
Opioid Overdose
Indicated for the complete or partial reversal of opioid depression (including respiratory depression) induced by natural and synthetic opioids
0.4-2 mg IV/IM/SC; repeat q2-3min PRN; not to exceed 10 mg (0.01 mg/kg)
Consider other causes of respiratory depression if desired response not achieved after administering 10 mg cumulative total
Endotracheal (this is the least desirable route of administration and supported only by anecdotal evidence): 2-2.5 times (0.8-5 mg) initial IV dose
For chronic opioid abuse, use smallest doses (0.1-0.2 mg) to avoid acute withdrawal; titrate to reversal of respiratory depression
Following reversal, additional dose(s) may need to be administered at later interval (ie, 20 to 60 min) depending on type and duration of opioid
Continuous IV infusion (Off-label)
- For use in patients exposed to long acting opioids (eg, methadone), sustained release products
- Calculate dose/hr based on effective intermittent dose used and duration of adequate response seen
- Alternatively, use two-thirds of initial effective naloxone bolus on an hourly basis (0.25-6.25 mg/hr); administer one-half of initial bolus dose 15 min after initiating continuous IV infusion to prevent drop in naloxone levels
Inhalation via Nebulization (Off-label)
- 2 mg as inhalation via nebulization; may repeat
- Switch to IV or IM administration when possible
- Nebulization method is not included in the AHA recommendations for initial management of opioid-associated life-threatening emergency
Evzio Auto-Injector
- Indicated for immediate administration as emergency treatment of known or suspected opioid overdose, as manifested by respiratory and/or central nervous system depression
- 0.4 mg or 2 mg IM/SC into anterolateral aspect of the thigh (through clothing if necessary)
- Seek emergency medical care immediately after use
- Additional doses may be administered q2-3min until EMS arrives
Dosing considerations (Evzio)
- Take-home, single-use auto-injector with visual and voice instruction for guidance
- May be prescribed to a family member or caregiver
- Compact size for portability with retractable needle system
- Intended for immediate administration as emergency therapy in settings where opioids may be present
- Not a substitute for emergency medical care
- Also see Administration
Reversal of Respiratory Depression with Therapeutic Opioid Doses
0.04-0.4 mg IV/IM/SC initially; may repeat until desired response achieved; if desired response not observed after 0.8 mg total, consider other causes of respiratory depression
Postoperative Opioid Depression
0.1-0.2 mg IV q2-3min to desired degree of reversal (eg, adequate ventilation and alertness without significant pain)
May repeat within 1-2hr intervals depending on amount, type (eg, short or long acting) and timing of last dose administered; supplemental IM doses have produced longer lasting effects
Dosage Forms & Strengths
injectable solution
- 0.4mg/mL
- 1mg/mL
IM/SC auto-injector
- 0.4mg/0.4mL (2 auto-injectors/package)
Opioid Reversal
Postanesthesia (acute) opioid reversal
- Neonates: 0.01 mg/kg IV into umbilical vein/IM/SC; give subsequent dose of 0.1 mg/kg if needed
- Children: 0.01 mg/kg IV once; may repeat with 0.1 mg/kg
Reversal of respiratory depression with therapeutic opioid dosing
- Manufacturer dosing: 0.005-0.01 mg; repeat q2-3min PRN based on response
- AAP dosing: 0.001-0.015 mg/kg/dose IV; titrate to effect
Acute opioid overdose
- ≤20 kg or <5 years: 0.1 mg/kg/dose IV/IM/SC/ET; if needed, repeat q2-3min PRN; not to exceed 2 mg/dose
- >20 kg or ≥5 years: 2 mg IV/IM/SC/ET; if needed, repeat q2-3min PRN
- Consider endotracheal administration when IV/intraosseous route not available; optimal endotracheal dose unknown; 2-3 times the IV dose recommended
Opioid Overdose (Evzio Auto-Injector)
Indicated for immediate administration as emergency treatment of known or suspected opioid overdose, as manifested by respiratory and/or central nervous system depression
0.4 mg or 2 mg IM/SC into anterolateral aspect of the thigh (through clothing if necessary); if child is <1 yr, pinch the thigh muscle while administering the dose
Seek emergency medical care immediately after use
Additional doses may be administered q2-3min until EMS arrives
Dosing considerations (Evzio)
- Take-home, single-use auto-injector with visual and voice instruction for guidance
- May be prescribed to a family member or caregiver
- Compact size for portability with retractable needle system
- Intended for immediate administration as emergency therapy in settings where opioids may be present
- Not a substitute for emergency medical care
- Also see Administration
Interactions
Interaction Checker
No Results

Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor

Adverse Effects
Frequency Not Defined
Withdrawal reaction precipitated
Abrupt reversal of narcotic depression may result in nausea, vomiting, sweating, tachycardia, increased blood pressure and tremulousness
Cardiac arrest
Ventricular fibrillation
Dyspnea
Pulmonary edema
Abdominal cramps
Diarrhea
Cardiac arrest
Hypertension
Hypotension
Ventricular tachycardia
Paresthesia
Restlessness
Shivering
Tonic-clonic seizures
Yawning
Diaphoresis
Piloerection
Hot flash
Myalgia
Tremor
Weakness
Rhinorrhea
Sneezing
Warnings
Contraindications
Hypersensitivity
Cautions
Caution in patients with cardiovascular disease or patients receiving medications with potential adverse cardiovascular effects
Caution in patients with history of seizures; avoid use in treatment of meperidine-induced seizures
Recurrence of respiratory depression may occur if opioid involved is long-acting or a partial agonist (eg, methadone, buprenorphine); observe patients until there is no further risk of recurrent respiratory or CNS depression
Avoid excessive dosages after use of opioids in surgery; abrupt postoperative reversal may unmask pain and may cause nausea, vomiting, sweating, seizures, hypertension, and tachycardia; other cardiovascular events, including pulmonary edema and arrhythmias may occur
Auto-injector (Evzio)
- Monitor injection site for residual needle parts and signs of infection when used to administered to infants <1year of age
Opioid withdrawal
- Use in patients who are opioid dependent may precipitate acute abstinence syndrome
- Syndrome characterized by body aches, diarrhea, tachycardia, fever, runny nose, sneezing, piloerection, sweating, yawning, nausea or vomiting, nervousness, restlessness, or irritability, shivering or trembling, abdominal cramps, weakness, and hypertension
- In neonates, opioid withdrawal may be life-threatening if not recognized and properly treated and may include convulsions, excessive crying, and hyperactive reflexes
Pregnancy & Lactation
Pregnancy category: C
Lactation: Not known if distributed in milk; use caution
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available.Pharmacology
Mechanism of Action
Competitive opioid antagonist; synthetic congener of oxymorphone
Absorption
Onset: 2 min (IV); 2-5 min (IM/SC)
Duration: Depends on route of administration; generally 1-2 hr
Elimination
Half-life: 30-90 min (adults); 3-4 hr (neonates)
Excretion: Urine
Administration
IV Compatibilities
Additive: Verapamil
Syringe: Heparin, ondansetron, dimehydrinate
Y-site: Fenoldopam, gatifloxacin, linezolid, propofol
IV Incompatibilities
Syringe: Pantoprazole
Y-site: Amphotericin B cholSO4
IV Preparation
For infusion, dilute to 4 mcg/mL in D5W or NS
Use within 24 hr
IM/SC Preparation
Before using, check to make sure the solution is not discolored
Replace if the solution is discolored or contains a precipitate
IM/SC Administration
For IM or SC use only
Seek emergency medical care immediately after use
Since the duration of action of most opioids exceeds that of naloxone and the suspected opioid overdose may occur outside of supervised medical settings, seek immediate emergency medical assistance, keep the patient under continued surveillance until emergency personnel arrive, and administer repeated naloxone doses as necessary
Evzio
- Administer in anterolateral aspect of the thigh in adult and pediatric patients
- Upon actuation, the autoinjector automatically inserts the needle IM or SC, and thereby delivers the naloxone injection, and then retracts the needle fully into its housing
- In pediatric patients aged <1 yr, the caregiver should pinch the thigh muscle while administering the dose
- Administer additional doses using a new auto-injector, if the patient does not respond or responds and then relapses into respiratory depression
- Additional doses may be given q2-3min until emergency medical assistance arrive
Storage
Store at controlled room temperature 15-25°C (59-77°F) excursions permitted between 4-40°C (39-104°F)
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Patient Handout
Formulary
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