It is available as an orally administered tablet and a long-acting injectable suspension.
Naltrexone is a non-opioid medication and is classified as an opioid antagonist.
This class of medication works by blocking opioid effects.
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Preliminary studies suggest naltrexone may provide benefits forchronic pain conditions(pain lasting longer than three months).
This article explains naltrexone’s effectiveness in treating various types of pain, such asmigraines,fibromyalgia, andneuropathy.
This prevents the opioids from affecting your body.
Opioids are highly addictive, mainly when used over long periods.
Naltrexone and Narcan, however, are used in different parameters and purposes.
Most notably, Narcan is FDA-approved to treat opioid overdose and reverse opioid-relatedrespiratory depression.
It is frequently used in emergencies and is available with a prescription and over-the-counter (OTC).
However, Narcan, by itself, is not used for pain management.
Nalmefene vs. Relistor
Like naloxone, nalmefene is FDA-approved to treat opioid overdose.
Relistor, conversely, is FDA-approved to treatopioid-induced constipation.
FDA-Approved Uses
Opioid antagonists are FDA-approved for the following uses:
What Is Naltrexone?
Naltrexone, an opioid antagonist, is FDA-approved for maintenance treatment of alcohol and OUDs in adults.
There are currently no FDA-approved indications for naltrexone use in the pediatric population.
Use In Other Products
Naltrexone is available in combination withContrave (bupropion)for weight loss.
How Does It Work?
Naltrexone works by blocking the effects of opioids produced in the body and introduced to the body.
There are some differences in how naltrexone works compared to other opioid antagonists, however.
Notably, naltrexone has a longer duration of action, allowing it to be used for long-term treatment.
In comparison, 6.9% (17.1 million American adults) experienced high-impact chronic pain.
Pain management can be challenging, but medications can help.
The following examines studies that reviewed the efficacy (effectiveness) of naltrexone for pain management.
The extent of pain relief varies and has not been generalized.
Data is limited, and results vary among individuals.
Neuropathy was the most common pain-related diagnosis with improvement in pain.
The study also found that symptoms may take several weeks to improve after starting therapy.
Levels of pain improvement were variable and differed based on pain-related diagnosis.
Data evaluating the use of low-dose naltrexone for fibromyalgia is conflicting.
Some studies demonstrate improvement in pain, but additional research is needed.
Naltrexone doses can have different impacts on the body.
Higher concentrations of naltrexone help with drug and alcohol addiction.
Low concentrations help reduce inflammation, making lower doses ideal for pain management.
At low doses, naltrexone blocks opioid receptors and promotes pain relief.
Studies assessing naltrexone for pain management specifically review it at low doses.
There are no studies evaluating high-dose naltrexone for pain management.
The dosage of naltrexone used to treat substance abuse is greater than the dose used for pain management.
Additional research is needed to explore further the efficacy of naltrexone for cancer and cancer-related pain.
However, low-dose (the dosing given for most conditions treated) naltrexone is typically well-tolerated.
The following outlines the common versus rare, severe side effects of naltrexone.
Pain, itching, or swelling at the injection site may occur with the injection formulation.
Severe Side Effects
Severe side effects may includeconfusion,hallucinations, andblurred vision.
However, it is not likely that naltrexone will cause liver damage when taken in recommended doses.
Your healthcare provider can discuss your risk and determine whether naltrexone is an appropriate treatment option.
Safe Consumption Guidelines
You should not use other opioids or alcohol while taking naltrexone.
However, no specific guidelines exist for how long you’ve got the option to safely take naltrexone.
However, studies show it may take up to three months to experience initial symptom improvement.
Duration of treatment may vary based on the treatment plan.
Naltrexone should not be used in pregnant or breastfeeding people unless otherwise instructed by a healthcare provider.
It is not approved for use in children.
It is essential to monitor for new or worsening depression and suicidal thoughts while taking this medication.
Autoimmune conditions such as MS or arthritis are often accompanied by chronic pain brought on by inflammation.
There are several different types of arthritis, and symptoms can vary.
A key feature of arthritis is pain, swelling, or stiffness around the joints.
Your healthcare provider may do additional testing to rule out autoimmune conditions.
Summary
Naltrexone is an opioid antagonist.
This class of medication works by blocking opioid effects.
Naltrexone is not FDA-approved for pain management, but it has been used off-label to treat chronic pain.
Naltrexone use requires close monitoring by your healthcare provider.
Let your provider know if you have recently stopped using opioids.
Do not stop taking naltrexone without discussing it with your healthcare provider.
Finally, if applicable, keep all medications out of reach of children and pets.
Chronic pain is defined as ongoing pain that lasts longer than three months.Naltrexone is used off-label for pain management.
It is FDA-approved to treat alcohol and opioid use disorders in adults.
Additional research is needed to assess its efficacy and place in therapy further.
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DailyMed.Label: codeine sulfate tablet.
DailyMed.Label: fentanyl citrate injection, solution.
DailyMed.Label: Hydrocodone bitartrate and acetaminophen tablet.
DailyMed.Label: oxycodone hydrochloride tablet.
DailyMed.Label: Naloxone hydrochloride injection, solution.
DailyMed.Label: nalmefene hydrochloride injection, solution.
DailyMed.Label: Relistor - methylnaltrexone bromide injection, solution.
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DailyMed.Label: Narcan- naloxone hydrochloride nasal spray.
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