Dosing & Uses
Dosage Forms & Strengths
injectable solution
- 0.4mg/mL
- 1mg/mL
injectable solution, high-dose
- 5mg/0.5mL prefilled syringe (Zimhi)
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
Zimhi High-Dose
- Indicated for immediate administration as emergency treatment of known or suspected opioid overdose, as manifested by respiratory and/or central nervous system depression
- 5 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
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
injectable solution, high-dose
- 5mg/0.5mL prefilled syringe (Zimhi)
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
Zimhi High-Dose
- Indicated for immediate administration as emergency treatment of known or suspected opioid overdose, as manifested by respiratory and/or central nervous system depression
- 5 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
Interactions
Interaction Checker
No Results

Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor

Contraindicated (0)
Serious - Use Alternative (2)
- naldemedine
naldemedine, naloxone. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Potential for additive opioid receptor anatagonism and increased risk of opioid withdrawal.
- naloxegol
naloxegol, naloxone. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Avoid coadministration; potential for additive effect of opioid receptor anatagonism and increased risk of opioid withdrawal.
Monitor Closely (0)
Minor (1)
- elvitegravir
elvitegravir decreases levels of naloxone by unknown mechanism. Minor/Significance Unknown. No dose adjustment of buprenorphine/naloxone is required upon coadministration with VITEKTA. Patients should be closely monitored for sedation and cognitive effects.
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
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
Peak plasma concentration: 17.2 ng/mL (5-mg dose); 3.58 ng/mL (2-mg dose)
AUC
- 0-inf: 26.6 ng⋅h/mL (5-mg IM dose); 9.97 ng⋅h/mL (2-mg IM dose)
- 0-0.04 h: 0.02 ng⋅h/mL (5-mg IM dose); 0.01 ng⋅h/mL (2-mg IM dose)
- 0-0.08 h: 0.15 ng⋅h/mL (5-mg IM dose); 0.04 ng⋅h/mL (2-mg IM dose)
Elimination
Excretion: Urine
Half-life
- 30-90 min (adults); 3-4 hr (neonates)
- 1.5 hr (5-mg IM dose); 1.86 hr (2-mg IM dose)
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
Administer into anterolateral aspect of the thigh (through clothing if necessary)
Child aged <1 yr: Pinch thigh muscle while administering the dose
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
Storage
Store at controlled room temperature 15-25°C (59-77°F) excursions permitted between 4-40°C (39-104°F)
Images
BRAND | FORM. | UNIT PRICE | PILL IMAGE |
---|---|---|---|
naloxone nasal - | 4 mg/actuation liquid | ![]() | |
Narcan nasal - | 4 mg/actuation liquid | ![]() | |
naloxone injection - | 1 mg/mL solution | ![]() | |
naloxone injection - | 1 mg/mL solution | ![]() | |
naloxone injection - | 0.4 mg/mL vial | ![]() | |
naloxone injection - | 0.4 mg/mL vial | ![]() | |
naloxone injection - | 0.4 mg/mL vial | ![]() | |
naloxone injection - | 0.4 mg/mL vial | ![]() | |
naloxone injection - | 0.4 mg/mL vial | ![]() | |
naloxone injection - | 0.4 mg/mL vial | ![]() | |
naloxone injection - | 0.4 mg/mL vial | ![]() | |
naloxone injection - | 0.4 mg/mL vial | ![]() | |
naloxone injection - | 0.4 mg/mL vial | ![]() | |
naloxone injection - | 0.4 mg/mL solution | ![]() | |
naloxone injection - | 0.4 mg/mL vial | ![]() | |
naloxone injection - | 0.4 mg/mL vial | ![]() | |
naloxone injection - | 0.4 mg/mL vial | ![]() | |
naloxone injection - | 0.4 mg/mL vial | ![]() |
Copyright © 2010 First DataBank, Inc.
Patient Handout
naloxone injection
NALOXONE - INJECTION
(nal-OX-one)
USES: Naloxone is used for the emergency treatment of known or suspected opioid overdose. Serious opioid overdose symptoms may include unusual sleepiness, unusual difficulty waking up, or breathing problems (ranging from slow/shallow breathing to no breathing). Other symptoms of overdose may include very small "pinpoint" pupils, slow heartbeat, or low blood pressure. If someone has serious overdose symptoms but you are not sure if the symptoms are due to opioid overdose, give naloxone right away anyway, since lasting slow/shallow breathing may cause permanent damage to the brain or death. Since symptoms of opioid overdose may return after treatment, be sure to get medical help right away after giving the first dose of naloxone.Naloxone belongs to a class of drugs known as opioid antagonists. It works by blocking the effects of the opioid in the brain.
HOW TO USE: This medication is given by injection into a muscle or under the skin. It may also be given by injection into a vein, usually by a health care professional.If you are using this medication at home, learn all preparation and usage instructions from your health care professional and the product package. Before using, check this product visually for particles or discoloration. If either is present, do not use the liquid. Learn how to store and discard medical supplies safely. Close family and household members should know the symptoms of an opioid overdose and be instructed on how to give naloxone if needed. Opioid overdose should be treated right away to prevent serious effects (such as brain damage). See also Uses section.The dosage is based on your medical condition and response to treatment.The effects of this medication are rapid but not long-lasting. After giving naloxone, get medical help right away, even if the person wakes up. If symptoms return after giving an injection, give another naloxone injection every 2 to 3 minutes. Continue to closely watch the person until emergency help is received. Tell the healthcare professional that you have given an injection of naloxone.
SIDE EFFECTS: Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.In someone who has been using an opioid regularly, withdrawal symptoms can happen suddenly after receiving this medication. Withdrawal symptoms may include body aches, fever, sweating, watering eyes, runny nose, sneezing, goose bumps, yawning, weakness, shivering/trembling, nervousness, restlessness, diarrhea, nausea/vomiting, stomach cramps, increased blood pressure, fast heartbeat. In babies younger than 4 weeks who have been receiving an opioid regularly, sudden opioid withdrawal may be life-threatening if not treated the right way. Symptoms in babies may include seizures, crying more than usual, and muscle twitching/spasms.A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
PRECAUTIONS: Before using naloxone, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: heart problems (such as irregular heartbeat, previous heart attack).Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).Since untreated opioid overdose can harm both a pregnant woman and her unborn baby, this medication may be used during pregnancy. However, naloxone may cause opioid withdrawal in your unborn baby. Tell your doctor right away that you used this medication, so you and your unborn baby can be monitored. Ask your doctor for details.It is unknown if this medication passes into breast milk. However, it is unlikely to harm a nursing infant. Consult your doctor before breast-feeding.
DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
OVERDOSE: Overdose in somebody not regularly taking an opioid is highly unlikely. However, if someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.
NOTES: Ask your doctor or pharmacist about ways to prevent opioid overdose. Teach your close family or household members the signs and symptoms of an opioid overdose and tell them where you keep this medication.
MISSED DOSE: Not applicable.
STORAGE: Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised August 2023. Copyright(c) 2023 First Databank, Inc.
IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
Formulary
Adding plans allows you to compare formulary status to other drugs in the same class.
To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.
Adding plans allows you to:
- View the formulary and any restrictions for each plan.
- Manage and view all your plans together – even plans in different states.
- Compare formulary status to other drugs in the same class.
- Access your plan list on any device – mobile or desktop.