Nalmefene: Patient drug information

What is this drug used for?

What do I need to tell my doctor BEFORE I take this drug?

If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
If you take drugs like methadone or buprenorphine to help you stop taking an opioid drug.
This is not a list of all drugs or health problems that interact with this drug.
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take this drug?

Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
If you are addicted to opioid drugs and are given this drug, you may have signs of withdrawal. If you have questions, talk with your doctor.
Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
Signs of high or low blood pressure like very bad headache or dizziness, passing out, or change in eyesight.
Shortness of breath.
Fast or abnormal heartbeat.
A burning, numbness, or tingling feeling that is not normal.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
All products:
Upset stomach or throwing up.
Nose spray:
Stuffy nose.
Nose or throat irritation.
Change in taste.
Decreased appetite.
Dry mouth.
Dry eyes.
Constipation.
Dizziness or headache.
Trouble sleeping.
Feeling tired or weak.
Anxiety.
Hot flashes.
Sweating.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to your national health agency.

How is this drug best taken?

Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.
Injection:
It is given as a shot into a vein.
Nose spray:
Do not take this drug by mouth. Use in your nose only. Keep out of your mouth and eyes (may burn).
Do not take this drug out of the container until you are ready to use it. Do not prime or test the spray before using it.
Be sure you know the signs of an overdose and when to use this drug. If you are not sure, talk with your doctor.
Be sure you know how to use before an emergency happens. Read the package insert and instructions for use that come with this drug. If you have any questions about how to use this drug, talk with the doctor or pharmacist.
Someone else may have to give this drug. Be sure others know where this drug is stored and how to give it if needed.
Call 911 or get emergency medical care right away after the first dose of this drug.
After using this drug, overdose symptoms may go away and come back. It is important to get medical help right away after using this drug.
Each device has only 1 dose and cannot be reused. If another dose is needed, you will need to use a new device.
If this drug expires, get a refill before a dose is needed.

What do I do if I miss a dose?

How do I store and/or throw out this drug?

Nose spray:
Store in the original container at room temperature.
Do not freeze.
Protect from heat and light.
Injection:
This drug will be given in a healthcare setting. You will not store it at home.
All products:
Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

General drug facts

If your symptoms or health problems do not get better or if they become worse, call your doctor.
Do not share your drugs with others and do not take anyone else's drugs.
Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Consumer Information Use and Disclaimer

This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider's examination and assessment of a patient's specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at https://www.wolterskluwer.com/en/know/clinical-effectiveness-terms.