Zurnai

Pronunciation: zur-nye
Generic name: nalmefene
Dosage form: injection for intramuscular or subcutaneous use
Drug class: Antidotes

Medically reviewed by Carmen Pope, BPharm. Last updated on Aug 12, 2024.

What is Zurnai?

Zurnai (nalmefene) is an opioid antagonist autoinjector that may be used for the emergency treatment of a known or suspected opioid overdose, in adults and children aged 12 years and older.

Zurnai can be used to reverse symptoms such as breathing problems, severe sleepiness, or unresponsiveness induced by natural or synthetic opioids.
It should be given right away and does not take the place of emergency medical care. Get emergency medical help immediately after giving the first dose of Zurnai, even if the person wakes up.

Zurnai works by occupying the same receptors in the brain as opioids, preventing opioids from binding and producing their effects. This reverses the dangerous effects of opioids and improves breathing, alertness, and blood pressure.

Zurnai gained FDA approval on 7 August 2024, as the first nalmefene autoinjector. Nalmefene was first approved as an injection formulation in 1995 under the brand name Revex (now discontinued) and in a nasal spray formulation under the brand name Opvee in 2023.

Zurnai uses and important information

Zurnai is used to temporarily reverse the effects of opioid medicines. The medicine in Zurnai is not expected to have an effect on people who are not taking opioid medicines. Always carry Zurnai with you in case of an opioid emergency.

Use Zurnai 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

Family members, caregivers, or other people who may have to use Zurnai in an opioid emergency should know where Zurnai is stored and how to give Zurnai before an opioid emergency happens. Make sure everyone reads the information contained in the carton as soon as you receive Zurnai.

Call 911 or get emergency medical help right away after giving the first dose of Zurnai. Rescue breathing or CPR (cardiopulmonary resuscitation) may be given while waiting for emergency medical help.

The signs and symptoms of an opioid emergency can return after Zurnai is given. If this happens, give additional doses of Zurnai every 2 to 5 minutes using a new Zurnai auto-injector for each dose and watch the person closely until emergency help arrives.

Zurnai side effects

The most common side effects of Zurnai include:

feeling hot
nausea
headache
dizziness
chills
vomiting
feeling pain from things that are not usually painful (allodynia)
irregular heartbeat (palpitations)
ringing in the ear
ear discomfort
feeling abnormal
burning sensation
hot flush
irritability.

These are not all of the possible side effects of Zurnai. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Serious side effects and warnings

Zurnai may cause the following serious side effects.

Sudden opioid withdrawal symptoms. In someone who has been using opioids regularly, opioid withdrawal symptoms can happen suddenly after receiving Zurnai and may include:

body aches
diarrhea
increased heart rate
fever
runny nose
sneezing
goosebumps
sweating
yawning
nausea or vomiting
nervousness
restlessness or irritability
shivering or trembling
stomach cramping
weakness
increased blood pressure.

Risk of opioid overdose. Zurnai blocks the effects of opioids and may cause opioid withdrawal in someone who has been using opioids regularly. Do not take large amounts of opioids to try to overcome the opioid-blocking effects of Zurnai. This could lead to an opioid overdose and death. Call 911 or get emergency medical help right away after using Zurnai.

It is not known if Zurnai is safe and effective in children younger than 12 years of age for the emergency treatment of known or suspected opioid overdose.

These are not all of the possible side effects of Zurnai. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Before taking

Do not use Zurnai if you are allergic to nalmefene hydrochloride or any of the ingredients in Zurnai.

Before using Zurnai, tell your healthcare provider about all of your medical conditions, including if you:

have heart problems
are pregnant or plan to become pregnant.
are breastfeeding or plan to breastfeed.

Pregnancy

It is not known if Zurnai will harm your unborn baby.

Breastfeeding

It is not known if Zurnai passes into your breast milk.

How should I use Zurnai?

Read the “Instructions for Use” in the Zurnai Package Insert for detailed information about the right way to use Zurnai. Use Zurnai exactly as prescribed by your healthcare provider.

Each Zurnai auto-injector contains only 1 dose of medicine and cannot be reused.
The Zurnai auto-injector is ready to use. Do not test or prime it before use.

Zurnai should be injected into the muscle (intramuscular) or underneath the skin (subcutaneous) of the outer thigh. It can be injected through your clothing if needed.

Administer additional doses of Zurnai, using a new autoinjector for each dose. If the patient does not respond or responds and then relapses into respiratory depression, additional doses of Zurnai may be given every 2 to 5 minutes until emergency medical assistance arrives.

Seek emergency medical care immediately after use.

Additional supportive and/or resuscitative measures may be helpful while awaiting emergency medical assistance.

What other drugs will affect Zurnai?

Tell your healthcare provider about the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Storage

Store Zunai at room temperature between 68°F to 77°F (20°C to 25°C).

Do not freeze or refrigerate.
Store in a clean dry place. Protect from light.
Keep in the carton until use.
During storage, check Zurnai through the viewing window of the auto-injector every 30 days. The liquid should be clear, colorless to light yellow. If the liquid is discolored, cloudy, or contains solid particles, replace it with a new Zurnai.
Check the expiration date. Replace Zurnai before the expiration date.

Keep Zurnai and all medicines out of the reach of children