provider image
Welcome! You’re in GoodRx for healthcare professionals. Now, you’ll enjoy a streamlined experience created specifically for healthcare professionals.
Skip to main content
Nalmefene Coupon - Nalmefene 2ml of 2mg/2ml vial

nalmefene

Generic
Used for Opioid Overdose
Used for Opioid Overdose

Nalmefene is an injectable medication that's used to reverse the effects of opioids or to manage opioid overdose. It's typically injected into the veins by a healthcare provider and only used in the hospital. Nalmefene works fast, but some people might require multiple doses.

Reviewed by:
reviewer
Yen Nguyen, PharmD
reviewer
Allison Gourley, PharmD
Last reviewed on September 22, 2022
BasicsSide effectsPros & consPharmacist tipsFAQsWarningsDosageAlternativesLatest newsImagesPricesMedicare
basics-icon

What is Nalmefene?

What is Nalmefene used for?

  • Reversing opioid effects, including slowed breathing

  • Managing opioid overdose

How Nalmefene works

Nalmefene is an opioid antagonist, which can help prevent or reverse the effects of opioids, including respiratory depression (slowed breathing), sedation (sleepiness), and low blood pressure.

Are you looking for information on naloxone (Narcan) or Opvee (nalmefene) nasal spray instead?

Drug Facts

Common BrandsRevex (brand no longer available)
Drug ClassOpioid antagonist
Controlled Substance ClassificationNot a controlled medication
Generic StatusLower-cost generic available
AvailabilityPrescription only
basics-icon

What are the side effects of Nalmefene?

The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.

Common Side Effects

  • Nausea (18%)
  • Vomiting (9%)
  • Fast heart rate (5%)
  • High blood pressure (5%)
  • Pain after surgery (4%)
  • Fever (3%)
  • Dizziness (3%)

Other Side Effects

  • Headache
  • Chills
  • Low blood pressure
  • Vasodilation (widening of blood vessels)

Source: DailyMed

The following side effects have also been reported

Side effects that you should report to your care team as soon as possible:

Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):

  • Chills
  • Dizziness
  • Headache
  • Irritability
  • Nausea
  • Vomiting
pros-and-cons

Pros and cons of Nalmefene

thumbs-up

Pros

Generally well-tolerated

Effects last longer than some other injectable opioid antagonists, such as naloxone (Narcan)

Don't need to adjust the dose for liver or kidney problems

thumbs-down

Cons

Has to be given by injection

Only available in the emergency room or hospital

Risk of opioid withdrawal symptoms

pharmacist-tips

Pharmacist tips for Nalmefene

pharmacist

  • If your body is dependent on opioids to function normally, you might experience withdrawal symptoms when getting nalmefene injections. Let your provider know if you experience signs of fast heart rate, nausea, vomiting, diarrhea, sweating, anxiety, agitation, dizziness, confusion, headache, trouble sleeping, or seizures.

    • Let your provider know if your breathing gets better after receiving nalmefene, but then gets worse again after your dose. Sometimes your breathing problems can come back, and you might need multiple doses.

      faqs

      Frequently asked questions about Nalmefene

      How is nalmefene given?
      Nalmefene is usually given into the vein by your healthcare provider. If your provider can't access your veins, then this medication can be given into the muscle or under the skin.
      How long does it take nalmefene to work?
      When nalmefene is given for suspected overdose, this medication has shown to reverse breathing problems within 2 to 5 minutes of injection in most people. When nalmefene is given to reverse the effects of opioids after surgery, it can take 5 to 20 minutes to work for most people. Your response to nalmefene can vary depending on the opioid dose and your body's opioid dependence level.
      What happens if nalmefene is given to people who didn't take opioids?
      Nalmefene hasn't been shown to have any effect when given to people who didn't take opioids. Nalmefene should only be given to people who are suspected to overdose on opioids. This medication won't have any effect in people if their symptoms of excessive sleepiness or slowed breathing aren't caused by opioids.
      Can nalmefene be given to me if I'm pregnant or breastfeeding?
      It's unknown if nalmefene can harm your baby. Let your provider know if you're pregnant or breastfeeding. They will determine if this medication is right for you.
      Will nalmefene raise the risk of tolerance, dependence, or abuse?
      No, nalmefene hasn't been shown to cause tolerance (when your body gets used to the medication), dependence (when your body depends on the medication to function), or abuse (when the medication is purposely used for a non-medical reason).
      GoodRxEducationalIcon

      How to save using GoodRx

      Compare Prices
      1. Compare PricesSpecify your dosage and quantity to find out exactly how much you can save.
      Select your free coupon
      2. Select your free couponYou can use the displayed coupon, or compare prices at other pharmacies near you.
      Show coupon to your pharmacist
      3. Show coupon to your pharmacistPresent your printed or electronic coupon when you pick up your prescription.
      Get free couponLearn more
      warings-icon

      What are the risks and warnings for Nalmefene?

      Nalmefene can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.

      risk-warning

      Risk of recurrent breathing problems

      Some people who accidentally overdose on a long-acting opioid, such as methadone or levo-alpha-acetylmethadol (LAAM), might have breathing problems that last for longer than the duration that nalmefene works. These breathing problems can be complicated and might require anesthetics, neuromuscular blockers, and other medications. Your provider will monitor you for a period of time after your nalmefene injection to make sure you don't have any recurring breathing problems. You'll need medical care and possibly more doses of nalmefene if your breathing problems return.

      risk-warning

      Risk of heart problems

      • Risk factors: Heart problems | Taking medications that affect the heart

        Medications that reverse the effects of opioids can affect the heart and lead to problems, such as changes in blood pressure and heart rhythm. While nalmefene have been used safely by people with heart problems in the past, you should let your provider know if you've heart probems. Also, let them know if you're taking other medications that can affect your heart. If so, they can monitor you properly.

        risk-warning

        Withdrawal effects

        • Risk factors: Higher opioid dose | Opioid dependence

          Opioid antagonists, such as nalmefene, can cause withdrawal symptoms in people who've been using opioids for a long time. The risk is higher for people who might rely on opioids to function normally, or take higher dose of opioids. Let your provider know right away if you experience withdrawal symptoms, such as high blood pressure, fast heart rate, nausea, vomiting, diarrhea, sweating, anxiety, agitation, dizziness, confusion, headache, trouble sleeping, or seizures.

          dosage

          Nalmefene dosage forms

          Typical dosing for Nalmefene

          Nalmefene is usually given in a hospital setting by a healthcare provider. The dose of nalmefene will be determined by your provider to manage your opioid overdose or to reverse the effects of opioids.

          alternatives

          What are alternatives to Nalmefene?

          There are a number of medications that your doctor can prescribe in place of Nalmefene. Compare a few possible alternatives below.
          Nalmefene
          Used for:

          • Reversing opioid effects, including slowed breathing

          • Managing opioid overdose

          View Prices
          Naloxone
          Used for:

          • Emergency treatment of opioid overdose in children and adults

          • Raising blood pressure in the case of septic shock - naloxone IV injection only

          • Post-surgery slowed breathing caused by opioids - naloxone IV injection only

          $44.39 Lowest GoodRx priceView Prices
          images

          Nalmefene images

          This medicine is Colorless Vial.

          Get savings updates for Nalmefene

          Receive price alerts, news, and other messages from GoodRx about Nalmefene and other healthcare topics and relevant savings offers.

          By signing up, I agree to GoodRx's Terms and Privacy Policy, and to receive marketing messages from GoodRx.

          Browse medications

          View All

          Research prescriptions and over-the-counter medications from A to Z, compare drug prices, and start saving.