Naltrexone Injection: MedlinePlus Drug Information

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Other drug names:	A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 0-9

Naltrexone Injection

(nal trex' one)

Contents of this page:
Why is this medication prescribed? How should this medicine be used? Other uses for this medicine What special precautions should I follow? What special dietary instructions should I follow? What should I do if I forget a dose?	What side effects can this medication cause? In case of emergency/overdose What other information should I know? Brand names

IMPORTANT WARNING: Return to top

Naltrexone injection may cause liver damage when given in large doses. It is not likely that naltrexone injection will cause liver damage when given in recommended doses. Tell your doctor if you have or have ever had hepatitis or liver disease. If you experience any of the following symptoms, call your doctor immediately: excessive tiredness, unusual bleeding or bruising, loss of appetite, pain in the upper right part of your stomach that lasts more than a few days, light-colored bowel movements, dark urine, or yellowing of the skin or eyes.

Talk to your doctor about the risks of receiving naltrexone injection.

Why is this medication prescribed? Return to top

Naltrexone injection is used along with counseling and social support to help people who have stopped drinking large amounts of alcohol to avoid drinking again. Naltrexone injection should not be used to treat people who are still drinking large amounts of alcohol. Naltrexone is in a class of medications called opiate antagonists. It works by decreasing the craving for alcohol.

How should this medicine be used? Return to top

Naltrexone injection comes as a solution (liquid) to be given by injection into the buttocks by a healthcare provider once every 4 weeks.

Naltrexone injection is only helpful when it is used as part of an addiction treatment program. It is important that you attend all counseling sessions, support group meetings, education programs or other treatments recommended by your doctor.

Naltrexone injection will not prevent withdrawal symptoms that may occur when you stop drinking alcohol after drinking large amounts for a long time.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

Other uses for this medicine Return to top

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow? Return to top

Before receiving naltrexone injection,

tell your doctor and pharmacist if you are allergic to naltrexone, any other medications, carboxymethylcellulose (an ingredient in artificial tears and some medications), or polylactide-co-glycolide (PLG; an ingredient in some injected medications). Ask your doctor or pharmacist if you don't know if a medication you are allergic to contains carboxymethylcellulose or PLG.
tell your doctor if you have taken any opioid medications including certain medications for diarrhea, cough, or pain within the last 7 to 10 days. Ask your doctor if you are not sure if a medication you have taken is an opioid. Also tell your doctor if you have used any opioid street drugs such as heroin within the last 7 to 10 days. Your doctor may order certain tests to see if you have recently taken any opioid medications or used opioid street drugs. Your doctor will not give you naltrexone injection if you have recently taken an opioid medication or used an opioid street drug.
do not take any opioid medications or use opioid street drugs during your treatment with naltrexone injection. Naltrexone injection blocks the effects of opioid medications and opioid street drugs. You may not feel the effects of these substances if you take or use them at low or normal doses. If you take or use higher doses of opioid medications or drugs during your treatment with naltrexone injection it could cause serious injury, coma (long lasting unconscious state), or death.
you should know that if you took opioid medications before your treatment with naltrexone injection, you may be more sensitive to the effects of these medications after you finish your treatment. After you finish your treatment, tell any doctor who may prescribe medication for you that you were previously treated with naltrexone injection.
tell your doctor what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
tell your doctor if you have or have ever had bleeding problems such as hemophilia, depression, or kidney disease.
tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while receiving naltrexone injection, call your doctor.
if you need medical treatment or surgery, including dental surgery, tell the doctor or dentist that you are receiving naltrexone injection. Wear or carry medical identification so that healthcare providers who treat you in an emergency will know that you are receiving naltrexone injection.
you should know that naltrexone injection may make you feel dizzy or drowsy. Do not drive a car or operate machinery until you know how this medication affects you.
you should know that people who drink large amounts of alcohol often become depressed and sometimes try to harm or kill themselves. Receiving naltrexone injection does not decrease the risk that you will try to harm yourself. You or your family should call the doctor right away if you experience symptoms of depression such as feelings of sadness, anxiousness, hopelessness, guilt, worthlessness, or helplessness, or thinking about harming or killing yourself or planning or trying to do so. Be sure that your family knows which symptoms may be serious so they can call the doctor right away if you are unable to seek treatment on your own.
talk to your doctor about the risks and benefits of naltrexone injection before you receive your first dose. Naltrexone will remain in your body for about 1 month after you receive the injection and cannot be removed before this time.

What special dietary instructions should I follow? Return to top

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose? Return to top

If you miss an appointment to receive naltrexone injection, schedule another appointment as soon as possible.

What side effects can this medication cause? Return to top

Naltrexone injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

nausea
vomiting
diarrhea
stomach pain
loss of appetite
dry mouth
headache
difficulty falling asleep or staying asleep
dizziness
drowsiness
anxiety
back or joint pain or stiffness
muscle cramps

Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately:

pain, swelling, tenderness, redness, hardness and/or itching at the injection site that gets worse over time
coughing
wheezing
shortness of breath
hives
rash
swelling of the eyes, face, mouth, lips, tongue, or throat
hoarseness
difficulty swallowing

Naltrexone injection may cause severe allergic pneumonia. Talk to your doctor about the risks of receiving this medication.

Naltrexone injection may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at http://www.fda.gov/MedWatch/index.html] or by phone [1-800-332-1088].

In case of emergency/overdose Return to top

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

Symptoms of overdose may include:

nausea
abdominal pain
drowsiness
dizziness

What other information should I know? Return to top

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response to naltrexone injection.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are receiving naltrexone injection.

Ask your doctor or pharmacist any questions you have about naltrexone injection.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names Return to top

Vivitrol®

Last Revised - 02/01/2009

American Society of Health-System Pharmacists, Inc. Disclaimer

AHFS^® Consumer Medication Information. © Copyright, 2009. The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.