SIDE EFFECTS: Nausea, headache, dizziness, anxiety, tiredness, and trouble sleeping may occur. In a small number of people, 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.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 taking naltrexone. Tell your doctor right away if any of these withdrawal symptoms occur: abdominal cramps, nausea/vomiting, diarrhea, joint/bone/muscle aches, mental/mood changes (e.g., anxiety, confusion, extreme sleepiness, visual hallucinations), runny nose.Naltrexone has rarely caused serious liver disease. The risk is increased when larger doses are used. Discuss the risks and benefits with your doctor. Stop using this medication and tell your doctor right away if you develop symptoms of liver disease, including: persistent nausea/vomiting, severe stomach/abdominal pain, dark urine, 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.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Quick GuideAddicted to Pills: The Health Risks of Drug Abuse
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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