Before you begin taking a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should take this medication.
Accidental ingestion: If you are dependent on narcotics and you accidentally ingest this medication, you could experience severe symptoms of withdrawal including confusion, nausea, shakiness, sweating, anxiety, visual hallucinations, vomiting, or diarrhea. Do not give this medication to anyone else, especially people who are dependent on opiate drugs.
Alcohol: You should not drink alcohol while taking this, medication as this could damage your liver.
Interference with opiate-containing mediations: Because this medication works by blocking the effects of opiates, it may interfere with other medications that contain opiates such as certain cough and cold medications, antidarrheal medications, and some analgesics (pain medications). Talk to your doctor or pharmacist about non-opiate containing alternatives.
Kidney function: If you have reduced kidney function your doctor may lower your dose of this medication. Your doctor may also request that you have regular kidney function tests while you are taking this medication.
Liver function: Naltrexone can cause liver injury. If you have reduced liver function your doctor may lower your dose of this medication. Your doctor may also request that you have regular liver function tests while you are taking this medication.
Overdose: If you accidentally overdose on this medication, seek medical attention immediately.
Suicide: People with substance abuse problems are at a higher risk of suicide. The use of naltrexone does not lower this risk.
Taking opioid drugs: If you attempt to overcome the blocking effects of naltrexone by taking opiates, this may result in breathing difficulties and death. Do not take opiates while you are on this medication. Furthermore, you may be more sensitive to lower doses of opiates after treatment with naltrexone. A smaller dose than previously used may be required to achieve the same effect.
Treatment of alcohol dependence: The use of naltrexone for the treatment of alcohol dependence has only been studied for a dosage regimen of 50 mg once daily for up to 12 weeks. The efficacy of naltrexone beyond 12 weeks in this population is not known.
Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: It is not known if naltrexone passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
Children: The safety and effectiveness of using this medication have not been established for children less than 18 years of age.