Naltrexone, sold under the brand name Revia among others, is a medication primarily used to manage alcohol or opioid use disorder by reducing cravings and feelings of euphoria associated with substance use disorder.It has also been found to be effective in the treatment of other addictions and may be used for them off-label.An opioid-dependent person should not receive naltrexone before detoxification.It is taken by mouth or by injection into a muscle.Effects begin within 30 minutes.A decreased desire for opioids may take a few weeks to occur.
Naltrexone has been best studied as a treatment for alcoholism.Naltrexone has been shown to decrease the amount and frequency of drinking.It does not appear to change the percentage of people drinking.Its overall benefit has been described as "modest.
Acamprosate may work better than naltrexone for eliminating drinking, while naltrexone may decrease the desire for alcohol to a greater extent.
The Sinclair method is a method of using opiate antagonists such as naltrexone to treat alcoholism. The person takes the medication once, about an hour before drinking, to avoid side effects that arise from chronic use.The opioid antagonist is thought to block the positive-reinforcement effects of alcohol and may assist the person to stop or reduce drinking.