From the Guidelines
Naltrexone is a valuable treatment option for opioid use disorder, particularly for highly motivated individuals, and should be considered as part of a comprehensive treatment plan that includes counseling and behavioral therapies. Naltrexone is an opioid antagonist medication that works by blocking opioid receptors in the brain, reducing cravings and the pleasurable effects associated with opioids 1. The medication is available in oral and extended-release injectable forms, with the latter being administered as a 380mg intramuscular injection once monthly 1.
When using naltrexone to treat opioid use disorder, it is essential to ensure that patients are opioid-free for 7-10 days before starting treatment to avoid precipitating withdrawal 1. Common side effects of naltrexone include nausea, headache, dizziness, anxiety, and fatigue, and liver function should be monitored during treatment as the medication can cause hepatotoxicity at higher doses 1.
According to recent guidelines, clinicians should offer or arrange evidence-based treatment, usually medication-assisted treatment with buprenorphine or methadone in combination with behavioral therapies, for patients with opioid use disorder 1. While naltrexone is not the first-line treatment for opioid use disorder, it can be a useful alternative for patients who are highly motivated and have access to counseling and behavioral therapies 1.
Key considerations when prescribing naltrexone include:
- Ensuring patients are opioid-free before starting treatment
- Monitoring liver function during treatment
- Providing counseling and behavioral therapies as part of a comprehensive treatment plan
- Considering alternative treatment options, such as buprenorphine or methadone, for patients who may not be suitable for naltrexone treatment 1.
Overall, naltrexone can be a valuable tool in the treatment of opioid use disorder, particularly when used as part of a comprehensive treatment plan that includes counseling and behavioral therapies.
From the FDA Drug Label
INDICATIONS AND USAGE Naltrexone Hydrochloride Tablets are indicated in the treatment of alcohol dependence and for the blockade of the effects of exogenously administered opioids. The main use of naltrexone is for the treatment of:
- alcohol dependence
- blockade of opioid effects It is also used for the treatment of opioid addiction. 2 3 2
From the Research
Naltrexone Overview
- Naltrexone is a broad opioid-receptor antagonist used in the management of alcohol dependence 4
- It has been shown to significantly reduce the risk of relapsing to heavy drinking compared to placebo 4
- Naltrexone is also used in the treatment of opioid dependence, with some studies indicating its effectiveness in reducing heroin use 5
Efficacy and Tolerability
- Meta-analyses have revealed that oral naltrexone is effective in reducing relapse to heavy drinking, but less effective in enhancing abstinence 4
- The effect size of naltrexone is modest, ranging from 0.15 to 0.2 4
- Naltrexone has a reasonable tolerability profile, with the most common side-effect being nausea 4
- Hepatotoxicity has not emerged as a clinical problem at the standard 50 mg dose, but is a concern at higher doses 4
Formulations and Administration
- Intramuscular versions of naltrexone, active for one month, have also shown efficacy in reducing alcohol consumption and craving 5
- Extended-release naltrexone (XR-NTX) is a once-a-month injectable formulation that offers a potentially more effective treatment option 6
- XR-NTX has been shown to be more efficacious and cost-effective than oral naltrexone in primary care settings 6
Comparison with Other Treatments
- Naltrexone has been compared to other treatments, including psychotherapy, benzodiazepines, and buprenorphine, with mixed results 7, 8
- Some studies have found naltrexone to be beneficial when combined with cognitive behavioural relapse prevention therapy in alcohol dependent patients 7
- However, other studies have found no statistically significant difference between naltrexone and other treatments, including placebo 8