Nalmefene (Nasal)

Generic name: nalmefene [ NAL-me-feen ]
Brand name: Opvee
Drug class: Antidotes

Medically reviewed by Drugs.com. Last updated on Nov 28, 2023.

Uses for nalmefene

Nalmefene nasal spray is used for emergency treatment of an opioid overdose or a possible overdose. It will temporarily reverse the effects of an opioid 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, not being able to respond, or a very small (pinpoint) pupil in a person who is difficult to awaken.

This medicine is available with your doctor's prescription.

Before using nalmefene

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies have not been performed on the relationship of age to the effects of nalmefene nasal spray in children younger than 12 years of age. Safety and efficacy have not been established.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of nalmefene nasal spray in the elderly. However, elderly patients are more likely to have age-related kidney, liver, or heart problems, which may require caution and an adjustment in the dose for patients receiving nalmefene nasal spray.

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

• Alfentanil
• Anileridine
• Benzhydrocodone
• Buprenorphine
• Butorphanol
• Codeine
• Dezocine
• Diacetylmorphine
• Difenoxin
• Dihydrocodeine
• Diphenoxylate
• Ethylmorphine
• Fentanyl
• Hydrocodone
• Hydromorphone
• Ketobemidone
• Levorphanol
• Meperidine
• Meptazinol
• Methadone
• Morphine
• Morphine Sulfate Liposome
• Nalbuphine
• Nicomorphine
• Opium
• Opium Alkaloids
• Oxycodone
• Oxymorphone
• Papaveretum
• Paregoric
• Pentazocine
• Piritramide
• Remifentanil
• Sufentanil
• Tapentadol
• Tilidine
• Tramadol

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

• Heart or blood vessel disease—Use with caution. May make these conditions worse.

Proper use of nalmefene

This medicine should be given immediately upon when a suspected or known overdose of an opioid has occurred. This will help prevent serious breathing problems and severe sleepiness that can lead to death.

This medicine is for use only in the nose. Do not get any of it in the eyes or on the skin. If it does get on these areas, rinse it off right away.

This medicine must be given to you (the patient) by someone else. Talk with people close to you so they know what to do in case of an emergency.

This medicine is not a substitute for emergency medical care. Call for emergency assistance after administering the first dose and keep the patient under continued surveillance.

This medicine comes with a patient information leaflet and patient instructions. It is very important that you read and understand this information. Be sure to ask your doctor about anything you do not understand.

To use the nasal spray:

• Remove the nasal spray from the box. Peel off the back from the top corner to open it.
• Do not prime or test the nasal spray. It contains a single dose of nalmefene and cannot be reused.
• Hold the nasal spray with your thumb on the white plunger and your fingers on either side of the nozzle.
• Lay the patient on their back. Support the patient's neck by your hand and allow the head to tilt back before giving this medicine.
• Gently insert the tip of the nozzle into one nostril of the patient, until your fingers on either side of the nozzle are against the bottom of the patient's nose.
• Press the plunger firmly to give the dose. Remove the nasal spray from the patient's nostril after giving the dose.
• 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. Use a new nasal spray for each dose and spray the medicine into the other nostril each time.

Dosing

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 12 years of age and older—At first, 2.7 milligrams (mg) (1 spray into one nostril). Another spray may be given into the other nostril every 2 to 5 minutes until the patient responds or until emergency medical assistance becomes available.
    • Children younger than 12 years of age—Use and dose must be determined by your doctor.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions while using nalmefene

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.

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.

Some types of opioid medications (eg, buprenorphine, pentazocine) may require larger or repeat doses of nalmefene to reverse the opioid effects.

Side Effects of nalmefene

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

• Blurred vision
• dizziness
• fast, pounding, or irregular heartbeat or pulse
• headache
• nervousness
• pounding in the ears

Less common

• Agitation
• anxiety
• confusion
• dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
• increased sweating
• unusual tiredness or weakness

Rare

• Chest pain or discomfort
• decrease in frequency of urination
• decrease in urine volume
• difficulty in passing urine
• discouragement
• feeling sad or empty
• irritability
• lack of appetite
• lack of interest or pleasure
• lightheadedness, dizziness, or fainting
• muscle twitching or jerking
• nervousness
• painful urination
• rhythmic movement of muscles
• shakiness in the legs, arms, hands, or feet
• sleepiness or unusual drowsiness
• slow or irregular heartbeat
• trembling or shaking of the hands or feet
• trouble breathing
• trouble concentrating
• trouble sleeping

Incidence not known

• Blue lips and fingernails
• blurred vision
• body aches
• coughing that sometimes produces a pink frothy sputum
• diarrhea
• excessive crying
• fever
• goosebumps
• headache
• increase in blood pressure
• increased or excessive unconscious or jerking movements
• nausea
• no blood pressure or pulse
• pale skin
• pounding in the ears
• restlessness
• runny nose
• seizures
• shivering
• sneezing
• stomach cramps
• stopping of the heart
• swelling in the legs and ankles
• unconsciousness
• vomiting
• yawning

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

• Feeling of warmth
• redness of the face, neck, arms and occasionally, upper chest

Less common

• Burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
• change in taste
• decreased appetite
• loss of taste
• stuffy nose
• throat and mouth pain
• throat irritation

Rare

• Dry mouth
• dryness or soreness of the throat
• hoarseness
• tender, swollen glands in the neck
• trouble in swallowing
• voice changes

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

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

Commonly used brand name(s)

In the U.S.

• Opvee

Available Dosage Forms:

• Spray

Therapeutic Class: Antidote

Pharmacologic Class: Opioid Antagonist

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer