Name: Narcan





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

Is this drug safe to take if I am pregnant or breastfeeding?

There are no adequate studies done on Naloxone to determine safe and effective use in pregnant women. It is not known whether Naloxone enters breast milk; therefore, it is best to be cautious before using it in women who are breastfeeding.

Side Effects of Narcan

Serious side effects have been reported with Narcan. See the “Narcan Precautions” section.

Common side effects of Narcan include the following:

  • Changes in heart rhythm
  • Shortness of breath
  • Reversal of analgesia
  • Nausea 
  • Vomiting
  • Sweating
  • Fast heart rate
  • Trembling
  • Seizures
  • Pulmonary Edema
  • Cardiac Arrest
  • Paraesthesia
  • Agitation
  • Hallucinations
  • Respiratory Depression
  • Hypoxia
  • Injection Site Reactions
  • Low blood pressure
  • Increased Blood Pressure
  • Hot flushes
  • Flushing

This is not a complete list of Narcan side effects. Ask your doctor or pharmacist for more information.

Tell your doctor if you have any side effect that bothers you or that does not go away.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.


The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For nasal dosage form (spray):
    • For opioid overdose:
      • Adults and children—At first, 4 milligrams (mg) (1 spray into one nostril). Another spray may be given into the other nostril every 2 to 3 minutes until the patient responds or until emergency medical assistance becomes available.

Interactions for Narcan

Specific Drugs




Cardiotoxic drugs

Serious adverse cardiovascular effects (e.g., ventricular tachycardia and fibrillation, pulmonary edema, cardiac arrest) resulting in death, coma, and encephalopathy reported in postoperative patients113 119 127

Use concomitantly with caution;113 monitor for hypotension, ventricular tachycardia or fibrillation, and pulmonary edema119 127


Methohexital appears to block the acute onset of withdrawal symptoms induced by naloxone in opiate addicts113

Narcan Pharmacokinetics



Rapidly inactivated following oral administration.b

Although effective orally, doses much larger than those required for parenteral administration are required for complete antagonism.b

Evzio auto-injector: Bioequivalent to naloxone hydrochloride administered by sub-Q or IM injection using a standard syringe.119 123

Narcan nasal spray: Time to peak plasma concentration similar to that observed following IM injection.127 Dose-normalized bioavailability approximately 43–54% that of IM dose.127 Peak plasma concentrations and AUC substantially higher following intranasal administration of a 2-mg dose as a single spray in one nostril (approximately 3.3- and 2.6-fold higher, respectively), a 4-mg dose as a single spray in one nostril (approximately 5.5- and 4.4-fold higher, respectively), a 4-mg dose as one 2-mg spray in each nostril (approximately 7.2- and 5.4-fold higher, respectively), or an 8-mg dose as one 4-mg spray in each nostril (approximately 11- and 8.7-fold higher, respectively) compared with a 0.4-mg IM dose.127


IV: Within 1–2 minutes.b

Sub-Q or IM: Within 2–5 minutes.b


Depends on the dose and route of administration and is more prolonged following IM than IV administration.113 119



Parenteral: Rapidly distributed into body tissues and fluids.113 119 123

Readily (within 2 minutes) crosses the placenta.113 119 127 g

Unknown whether distributed into milk.113 119 127 g

Plasma Protein Binding

Weakly bound to plasma proteins (mainly albumin).113 119 127



Rapidly metabolized in the liver, principally by conjugation with glucuronic acid.113 119 127

Major metabolite is naloxone-3-glucuronide.113 119 127

Also undergoes N-dealkylation and reduction of the 6-keto group followed by conjugation.b

Elimination Route

Oral or IV dose: 25–40% excreted as metabolites in urine in 6 hours, about 50% in 24 hours, and 60–70% in 72 hours.113 119 127


Adults: 30–81 minutes.113

Neonates: About 3 hours.113

Evzio auto-injector: 1.28–1.5 hours.119

Narcan nasal spray: 1.9–2.1 hours.127 129

Advice to Patients

  • Instruct patients receiving naloxone auto-injector or nasal spray and their family members or caregivers about clinical manifestations requiring naloxone administration and proper administration techniques.119 127 Encourage familiarity with the auto-injector training device provided in each carton; however, advise that untrained individuals should still attempt to use the auto-injector in case of suspected opiate overdosage.119

  • Repeated doses may be required; importance of using a new auto-injector or nasal spray unit for each dose.119 127

  • Seek immediate medical attention after administering naloxone in an out-of-hospital setting.119 127 Monitor patient closely until emergency care arrives.119 127

  • Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as any concomitant illnesses.

  • Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.

  • Importance of informing patients of other important precautionary information. (See Cautions.)

Uses For Narcan

Naloxone injection is used to treat an opioid emergency such as an overdose or a possible overdose of a narcotic medicine. Some signs and symptoms of an opioid emergency are breathing problems (which can range from slow or shallow breathing to no breathing), extreme sleepiness, slow heartbeat, or not being able to respond.

This medicine is available only with your doctor's prescription.

Precautions While Using Narcan

This medicine should be given immediately after a suspected or known overdose of an opioid or narcotic medicine. This is to prevent a serious condition called respiratory or central nervous system depression.

Severe opioid withdrawal symptoms may happen suddenly after receiving this medicine. These include body aches, a fever, sweating, runny nose, sneezing, goose bumps, yawning, weakness, shivering or trembling, nervousness, restlessness or irritability, diarrhea, nausea or vomiting, stomach cramps, fast heartbeat, and increased blood pressure.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Patient information

Narcan (nar´ kan)
(naloxone hydrochloride)
Nasal Spray

You and your family members or caregivers should read this Patient Information leaflet before an opioid emergency happens. This information does not take the place of talking with your healthcare provider about your medical condition or your treatment.
What is the most important information I should know about Narcan Nasal Spray?
Narcan Nasal Spray is used to temporarily reverse the effects of opioid medicines. The medicine in Narcan Nasal Spray has no effect in people who are not taking opioid medicines. Always carry Narcan Nasal Spray with you in case of an opioid emergency.
1. Use Narcan Nasal Spray right away if you or your caregiver think signs or symptoms of an opioid emergency are present, even if you are not sure, because an opioid emergency can cause severe injury or death. Signs and symptoms of an opioid emergency may include:
• unusual sleepiness and you are not able to awaken the person with a loud voice or by rubbing firmly on the middle of their chest (sternum)
• breathing problems including slow or shallow breathing in someone difficult to awaken or who looks like they are not breathing
• the black circle in the center of the colored part of the eye (pupil) is very small, sometimes called “pinpoint pupils,” in someone difficult to awaken
2. Family members, caregivers, or other people who may have to use Narcan Nasal Spray in an opioid emergency should know where Narcan Nasal Spray is stored and how to give Narcan before an opioid emergency happens.
3. Get emergency medical help right away after giving the first dose of Narcan Nasal Spray. Rescue breathing or CPR (cardiopulmonary resuscitation) may be given while waiting for emergency medical help.
4. The signs and symptoms of an opioid emergency can return after Narcan Nasal Spray is given. If this happens, give another dose after 2 to 3 minutes using a new Narcan Nasal Spray and watch the person closely until emergency help is received.
What is Narcan Nasal Spray?
• Narcan Nasal Spray is a prescription medicine used for the treatment of an opioid emergency such as an overdose or a possible opioid overdose with signs of breathing problems and severe sleepiness or not being able to respond.
• Narcan Nasal Spray is to be given right away and does not take the place of emergency medical care. Get emergency medical help right away after giving the first dose of Narcan Nasal Spray, even if the person wakes up.
• Narcan Nasal Spray is safe and effective in children for known or suspected opioid overdose.
Who should not use Narcan Nasal Spray?
Do not use Narcan Nasal Spray if you are allergic to naloxone hydrochloride or any of the ingredients in Narcan Nasal Spray. See the end of this leaflet for a complete list of ingredients in Narcan Nasal Spray.
What should I tell my healthcare provider before using Narcan Nasal Spray?
Before using Narcan Nasal Spray, tell your healthcare provider about all of your medical conditions, including if you:
• have heart problems
• are pregnant or plan to become pregnant. Use of Narcan Nasal Spray may cause withdrawal symptoms in your unborn baby. Your unborn baby should be examined by a healthcare provider right away after you use Narcan Nasal Spray.
• are breastfeeding or plan to breastfeed. It is not known if Narcan Nasal Spray passes into your breast milk.

Tell your healthcare provider about the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.
How should I use Narcan Nasal Spray?
Read the “Instructions for Use” at the end of this Patient Information leaflet for detailed information about the right way to use Narcan Nasal Spray.
• Use Narcan Nasal Spray exactly as prescribed by your healthcare provider.
• Each Narcan Nasal Spray contains only 1 dose of medicine and cannot be reused.
• Narcan Nasal Spray comes in a 2 mg and 4 mg strength. Your healthcare provider will prescribe the one that is right for you.
• Lay the person on their back. Support their neck with your hand and allow the head to tilt back before giving Narcan Nasal Spray.
• Narcan Nasal Spray should be given into one nostril.
• If additional doses are needed, give Narcan Nasal Spray in the other nostril.
What are the possible side effects of Narcan Nasal Spray?
Narcan Nasal Spray may cause serious side effects, including:
• Sudden opioid withdrawal symptoms. In someone who has been using opioids regularly, opioid withdrawal symptoms can happen suddenly after receiving Narcan Nasal Spray and may include:
o body aches
o diarrhea
o increased heart rate
o fever
o runny nose o sneezing
o goose bumps
o sweating
o yawning
o nausea or vomiting o nervousness
o restlessness or irritability
o shivering or trembling
o stomach cramping
o weakness
o increased blood pressure

In infants under 4 weeks old who have been receiving opioids regularly, sudden opioid withdrawal may be life-threatening if not treated the right way. Signs and symptoms include: seizures, crying more than usual, and increased reflexes.

These are not all of the possible side effects of Narcan Nasal Spray. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
How should I store Narcan Nasal Spray?
• Store Narcan Nasal Spray at room temperature between 59°F to 77°F (15°C to 25°C). Excursions permitted up to 104°F (40°C).
• Do not freeze Narcan Nasal Spray.
• Keep Narcan Nasal Spray in its box until ready to use. Protect from light.
• Replace Narcan Nasal Spray before the expiration date on the box.

Keep Narcan Nasal Spray and all medicines out of the reach of children.
General information about the safe and effective use of Narcan Nasal Spray.
Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. Do not use Narcan Nasal Spray for a condition for which it was not prescribed. You can ask your pharmacist or healthcare provider for information about Narcan Nasal Spray that is written for health professionals.
What are the ingredients in Narcan Nasal Spray?
Active ingredient: naloxone hydrochloride
Inactive ingredients: benzalkonium chloride (preservative), disodium ethylenediaminetetraacetate (stabilizer), sodium chloride, hydrochloric acid to adjust pH and sterile water
Narcan Nasal Spray is not made with natural rubber latex.

Distributed by Adapt Pharma, Inc., Radnor, PA 19087 USA.
For more information, go to or call 1-844-4Narcan (1-844-462-7226).

This Patient Information has been approved by the U.S. Food and Drug Administration. Issued: 02/2017