This medication is used to treat alcohol abuse. It is used only in people who have been able to stop drinking for some time before starting treatment with naltrexone. You should not be drinking when you start naltrexone. It can help people drink less alcohol or stop drinking altogether. Naltrexone works in the brain to decrease the desire to drink. It does not work like some other treatments for alcohol abuse (e.g., disulfiram). It will not make you sick when taken with alcohol.
This medication is also used to prevent relapse to opioid abuse, after opioid detoxification. It works by blocking the action of opioids. This medication must not be used in people currently taking opiates, including methadone. Doing so can cause sudden withdrawal symptoms.
Naltrexone belongs to a class of drugs known as opiate antagonists. It is used as part of a complete treatment program for alcohol or opioid abuse (e.g., counseling, 12-step program, lifestyle changes).
How to use Naltrexone Microspheres Suspension, Extended Release, Reconstituted (Suspension, ER, Reconstituted)
Before you receive this medication, you should have a urine test to check for recent opiate drug use. Your doctor may give you another medication (naloxone challenge test) to check for opiate use. Do not use alcohol/any opiates for at least 7 days before starting naltrexone. You may need to stop certain opiate drugs (such as methadone) 10 to 14 days before starting naltrexone.
This medication is injected into a muscle in the buttock by a health care professional. It is given as directed by your doctor, usually once a month.
Dosage is based on your medical condition and response to treatment. Your doctor may start you at a lower dose and monitor you for any side effects or withdrawal symptoms before increasing your dose.
To get the most benefit from this medication, use it regularly and continue your treatment program. To help you remember, mark your calendar with the days you need to receive this drug and/or be treated.
Tell your doctor if you start drinking alcohol again or start using drugs.
Nausea, headache, dizziness, drowsiness, anxiety, tiredness, and loss of appetite may occur. If you have been using opiates regularly, mild opiate withdrawal symptoms may occur, including abdominal cramps, restlessness, bone/joint pain, muscle aches, and runny nose. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.
Pain/redness/swelling/itching/bruising at the injection site may also occur. If any of these effects steadily worsen, or if they persist longer than two weeks, tell your doctor or pharmacist right away. Rarely, a severe injection site reaction can cause permanent injury if not treated.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Sudden opiate withdrawal symptoms can occur within minutes after using naltrexone if you are physically addicted to opiates. Tell your doctor right away if any of these withdrawal symptoms occur: vomiting, diarrhea, mental/mood changes (e.g., anxiety, confusion, extreme sleepiness, visual hallucinations).
Tell your doctor right away if you have any serious side effects, including: fast/irregular heartbeat, depression/rare thoughts of suicide, signs of a serious breathing problem/pneumonia (e.g., cough, shortness of breath, wheezing), blisters/sores at injection site.
Get medical help right away if this rare but very serious side effect occurs: chest pain.
Naltrexone may rarely cause serious liver disease. The risk is increased when larger doses are used. Stop using this medication and get medical help right away if you have any symptoms of liver damage, including: dark urine, persistent nausea/vomiting/loss of appetite, stomach/abdominal pain, yellowing eyes/skin.
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Before using naltrexone, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: current or recent use (in the last 7 to 14 days) of any type of opioid drug (such as morphine, methadone, buprenorphine), bleeding problems (such as hemophilia, low platelets), kidney disease, liver problems.
You should carry or wear medical identification stating that you are using this drug so that appropriate treatment can be given in a medical emergency. See also Medical Alert section.
This drug may make you dizzy or drowsy. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).
After stopping naltrexone treatment or missing a dose of naltrexone, you may be more sensitive to lower doses of opioids, increasing your risk of serious, possibly fatal side effects from the opioid (such as decreased breathing, loss of consciousness). You may also be more sensitive to lower doses of opioids near the end of the month that you received naltrexone treatment.
Before having surgery or any medical/dental treatment, tell your doctor or dentist that you are using this medication.
This medication blocks the effects of opiate drugs (including heroin) and similar drugs (opioids). However, large doses of heroin or opioids can overcome this block. Trying to overcome this block is very dangerous and may cause serious injury, loss of consciousness, and death. Make sure you completely understand and accept the risks and benefits of using this medication. Follow your doctor's instructions closely.
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
This drug passes into breast milk. Consult your doctor before breast-feeding.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Some products that may interact with this drug include: "blood thinners" (such as warfarin, enoxaparin), dextromethorphan, diarrhea medication (such as diphenoxylate), opioid pain or cough relievers (such as codeine, hydrocodone).
This medication may interfere with certain laboratory tests (including drug tests), possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this drug.
If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.
Do not share this medication with others.
Laboratory and/or medical tests (e.g., liver function tests) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.
See also Precautions section.
Not applicable. This medication is given in a clinic or doctor's office and will not be stored at home.Information last revised September 2020. Copyright(c) 2020 First Databank, Inc.
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