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Naltrexone Important Safety Information | WW USA

Important Naltrexone HCI Safety Information

Most Important Safety Information

Vulnerability to opioid overdose. Patients who have been treated with naltrexone HCL may respond to lower doses of opioids than previously used.

Hepatoxicity. Cases of hepatitis and clinically significant liver dysfunction were observed in association with naltrexone HCL exposure. Seek medical attention if you experience symptoms of acute hepatitis.

Depression and suicidality. Depression, suicide, attempted suicide and suicidal ideation have ben reported in experience with naltrexone HCL used in the treatment of opioid dependence. Report any symptoms of depression or suicidality to your healthcare provider.

What is the FDA-approved use of Naltrexone HCI?

Naltrexone is a prescription medication that is FDA-approved:

  • to treat alcohol dependence
  • for the blockade of the effects of exogenously administered opioids. To prevent relapse to opioid dependence after opioid detoxification.

Limitations of Use:

You should stop drinking alcohol or using opioids before starting this medicine. To avoid precipitated opioid withdrawal, it is recommended you should have an opioid-free interval of a minimum of 7 to 10 days if previously dependent on short-acting opioids.

What should I tell my provider before using Naltrexone HCI?

Drugs you are taking. It’s important to tell your provider all of the medications you are currently taking, including prescription, over-the-counter medications, vitamins, and herbal and dietary supplements.

Your entire medical history. In particular, tell your provider if you have a past history of:

  • bleeding problems such as hemophilia; or
  • liver or kidney disease.
  • have alcohol dependence and use opioids.
  • Depression, Suicidal thoughts or behavior

Whether you are pregnant or plan to become pregnant. Talk to your healthcare provider about the risk to your unborn baby if you take Naltrexone HCI during pregnancy, and about registering with the National Pregnancy Registry by calling 1-844-405-6185 are breastfeeding. Naltrexone HCI may be passed into your breast milk based on certain animal studies.

Withholding or providing inaccurate information about your health and medical history in order to obtain treatment may result in harm, including, in some cases, death.

What drug interactions do I need to be aware of?

Some medications to watch out for include:

  • Opioid-containing medicines for pain, cough or colds
  • Avoid using opioids and/or alcohol during treatment with Naltrexone HCI in order to avoid overdose.
  • Other oral opioid analgesic medications.

What are the most common side effects that I should be aware of when taking Naltrexone HCI?

If you are experiencing a medical emergency, call 911 or seek immediate medical attention.

  • Nausea
  • Vomiting
  • Loss of appetite
  • Joint pain
  • Muscle cramps
  • Headache
  • Dizziness
  • Drowsiness
  • Sleep problems (insomnia)
  • Tooth pain
  • Cold symptoms such as stuffy nose, sneezing, sore throat
  • Feeling anxious or nervous

You are encouraged to report negative side effects of prescription products:

Contact FDA MedWatch at 1-800-FDA-1088 or visit fda.gov/medwatch

This information is not comprehensive. Please see the full Prescribing Information for complete safety information.