Nalmefene (By injection)
Nalmefene Hydrochloride (NAL-me-feen hye-droe-KLOR-ide)
Treats opioid overdose in an emergency situation. Must be given as soon as possible.
Brand Name(s):
There may be other brand names for this medicine.When This Medicine Should Not Be Used:
This medicine is not right for everyone. Do not use it if you had an allergic reaction to nalmefene.How to Use This Medicine:
Injectable
- This medicine should be given right away after a suspected or known overdose of an opioid medicine. This will help prevent serious breathing problems and severe sleepiness that can lead to death.
- The effects of the opioid medicine may last longer than the effects of the nalmefene. This means the breathing problems and sleepiness could come back. Always call for emergency help after the first dose of nalmefene.
- Nalmefene injection:
- This medicine is given as a shot under your skin or into a muscle.
- A nurse or other health provider will give you this medicine.
- Zurnai® autoinjector: A home health caregiver or a family member will give you or your child this medicine. It may be given as a shot under your skin or into a muscle of the outer thigh, through clothing if needed. Do not inject into any other area of the body.
- To use the autoinjector:
- Do not test or prime the autoinjector before use. This medicine can only be used one time.
- Check the liquid in the autoinjector. It should be clear, colorless to light-yellow. Do not use this medicine if it is cloudy, discolored, or has particles in it. Do not use it if it is broken or the blue cap is missing.
- Twist the blue cap counterclockwise to break the safety seal and pull straight off to remove the cap. Do not replace the cap after it has been removed. Do not touch the needle.
- Place the needle guard against the outer thigh. Push the autoinjector firmly down against the outer thigh until you hear a "click". Hold in place for 3 seconds. The viewing window should turn completely orange (fully blocked). Remove the autoinjector.
- Move the patient on their side (recovery position) after giving the medicine and get emergency medical help right away.
- Watch the patient closely. You may also give additional doses to the patient every 2 to 5 minutes until the patient responds or emergency medical assistance becomes available. Give a new nalmefene injection for each dose.
- Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.
- Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
Drugs and Foods to Avoid:
Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
Warnings While Using This Medicine:
- Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, or heart or blood vessel disease.
- This medicine could cause withdrawal symptoms from the opioid medicine.
- Nalmefene injection may not be able to completely reverse the opioid effects (including respiratory depression) of buprenorphine and pentazocine.
- Keep all medicine out of the reach of children. Never share your medicine with anyone.
Possible Side Effects While Using This Medicine:
Call your doctor right away if you notice any of these side effects:
- Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
- Blue lips and fingernails, chest pain, increased sweating, trouble breathing, swelling in the legs and ankles
- Blurred vision, headache, fast, pounding, or uneven heartbeat
- Diarrhea, nausea, vomiting, stomach cramps or pain
- Lightheadedness, dizziness, fainting
- Seizures, shaking, or feeling restless, nervous, or irritable
- Unusual tiredness or weakness
If you notice these less serious side effects, talk with your doctor:
- Fever, chills
- Nausea, vomiting
- Ringing, buzzing, or other unexplained noise in the ears, hearing loss
- Warmth or redness in your face, neck, arms, or upper chest
If you notice other side effects that you think are caused by this medicine, tell your doctor
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088
Last Updated: 2/4/2025