Naltrexone may cause liver damage when taken in large doses. It is not likely that naltrexone will cause liver damage when taken 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, stop taking naltrexone and 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.
Keep all appointments with your doctor and the laboratory. Your doctor may order certain laboratory tests to check your body's response to naltrexone.
Talk to your doctor about the risks of taking naltrexone.
Naltrexone is used along with counseling and social support to help people who have stopped drinking alcohol and using street drugs continue to avoid drinking or using drugs. Naltrexone should not be used to treat people who are still using street drugs or drinking large amounts of alcohol. Naltrexone is in a class of medications called opiate antagonists. It works by decreasing the craving for alcohol and blocking the effects of opiate medications and opioid street drugs.
Naltrexone comes as a tablet to take by mouth either at home or under supervision in a clinic or treatment center. When naltrexone is taken at home, it is usually taken once a day with or without food. When naltrexone is taken in a clinic or treatment center, it may be taken once a day, once every other day, once every third day, or once every day except Sunday. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take naltrexone exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Naltrexone 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 will help you avoid using drugs and alcohol, but it will not prevent or relieve the withdrawal symptoms that may occur when you stop using these substances. Instead, naltrexone may cause or worsen withdrawal symptoms. You should not take naltrexone if you have recently stopped using opioid medications or opioid street drugs and are now experiencing withdrawal symptoms.
Naltrexone will help you avoid drugs and alcohol only as long as you are taking it. Continue to take naltrexone even if you feel well. Do not stop taking naltrexone without talking to your doctor.
This medication may be sometimes prescribed for other uses; ask your doctor or pharmacist for more information.
Before taking naltrexone,
Unless your doctor tells you otherwise, continue your normal diet.
Take the missed dose as soon as you remember it. However, if it is almost time for your next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
Naltrexone may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
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:
Naltrexone may cause other side effects. Call your doctor if you have any unusual problems while taking 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 ( Web Site) or by phone (1-800-332-1088).
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).
It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. Web Site
Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ( Web Site) for more information if you do not have access to a take-back program.
In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at Web Site. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.
Before having any laboratory tests, tell your doctor and the laboratory personnel that you are taking naltrexone.
Ask your doctor or pharmacist any questions you have about naltrexone.
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.