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Generic Name: nalmefene (NAL-me-feen)
Brand Name: Revex
Nalmefene is used for:
Completely or partially reversing the effects of narcotics and managing known or suspected overdose of narcotics. It may also be used for other conditions as determined by your doctor.
Nalmefene is a narcotic antagonist. It works by blocking opiate receptor sites, which reverses or prevents toxic effects of narcotic (opioid) analgesics.
Do NOT use nalmefene if:
- you are allergic to any ingredient in nalmefene
Contact your doctor or health care provider right away if any of these apply to you.
Before using nalmefene:
Some medical conditions may interact with nalmefene. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have heart disease or a history of substance abuse
- if you have recently had surgery
Some MEDICINES MAY INTERACT with nalmefene. Tell your health care provider if you are taking any other medicines, especially any of the following:
- Flumazenil because the risk of seizures may be increased
This may not be a complete list of all interactions that may occur. Ask your health care provider if nalmefene may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use nalmefene:
Use nalmefene as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Nalmefene is usually administered as an injection at a hospital or clinic.
- If nalmefene contains particles or is discolored, or if the vial is cracked or damaged in any way, do not use it.
- Keep this product, as well as syringes and needles, out of the reach of children. Do not reuse needles, syringes, or other materials. Dispose of properly after use. Ask your doctor or pharmacist to explain local regulations for proper disposal.
- If you miss a dose of nalmefene, use it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not use 2 doses at once.
Ask your health care provider any questions you may have about how to use nalmefene.
Important safety information:
- Nalmefene may cause dizziness or drowsiness. Do not drive, operate machinery, or do anything else that could be dangerous until you know how you react to nalmefene. Using nalmefene alone, with certain other medicines, or with alcohol may lessen your ability to drive or to perform other potentially dangerous tasks.
- If you experience a return of symptoms (such as drowsiness or difficulty breathing), contact your doctor immediately.
- Use nalmefene with caution in the ELDERLY because they may be more sensitive to its effects.
- Use nalmefene with extreme caution in NEWBORNS of women who may have had dependency on narcotics. Opioid withdrawal may occur.
- Use nalmefene with extreme caution in CHILDREN. Safety and effectiveness have not been confirmed.
- PREGNANCY and BREAST-FEEDING: If you become pregnant, discuss with your doctor the benefits and risks of using nalmefene during pregnancy. It is unknown if nalmefene is excreted in breast milk. If you are or will be breast-feeding while you are using nalmefene, check with your doctor or pharmacist to discuss the risks to your baby.
If you are addicted to narcotics and are given nalmefene, you may experience WITHDRAWAL symptoms, including abnormal skin sensations; anxiety; diarrhea; fever; goose bumps; nausea; pain; rapid heartbeat; rigid muscles; runny nose; seeing, hearing, or feeling things that are not there; shivering or tremors; sneezing; sweating; trouble sleeping; and vomiting.
Possible side effects of nalmefene:
All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:
Dizziness; nausea; vomiting.
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); fainting; fast, slow, or irregular heartbeat; fever; flushing; heart rhythm changes; seizures; severe or persistent headache or dizziness; shortness of breath; sudden chest pain.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately.Proper storage of nalmefene:
Nalmefene is usually handled and stored by a health care provider. If you are using nalmefene at home, store nalmefene as directed by your pharmacist or health care provider. Keep nalmefene out of the reach of children and away from pets.
- If you have any questions about nalmefene, please talk with your doctor, pharmacist, or other health care provider.
- Nalmefene is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
- Check with your pharmacist about how to dispose of unused medicine.
This information is a summary only. It does not contain all information about nalmefene. If you have questions about the medicine you are taking or would like more information, check with your doctor, pharmacist, or other health care provider.