Naltrexone Treatment for Alcoholism and Addiction

How it Blocks the Effects of Opioids and Reduces Alcohol Craving

Man Getting Pill From Bottle
Naltrexone Blocks Effects of Some Drugs. © Getty Images

Naltrexone is an opioid receptor antagonist used primarily in the management of alcohol dependence and opioid addiction. Naltrexone hydrochloride is sold under the brand names Revia and Depade. An extended-release form of Naltrexone is marketed under the trade name Vivitrol.


For people who have stopped drinking, Naltrexone reduces the craving for alcohol that many alcohol dependent people experience when they quit drinking. It is not fully understood how Naltrexone reduces the craving for alcohol, but some scientists believe it works by decreasing the reinforcing effects of alcohol in certain neural pathways in the brain. This mechanism involves the neurotransmitter dopamine.

Naltrexone works by blocking the effects of drugs like heroin and cocaine in the brain, too. As an opioid receptor antagonist, Naltrexone simply blocks the normal reaction of the part of the brain that produces the feeling of pleasure that opioids produce.


In pill form, Naltrexone is usually prescribed to be taken once a day. Studies have looked at the use of Naltrexone over a 12-week period to help people who have stopped drinking to reduce the craving for alcohol during the early days of abstinence when the risk of a relapse is the greatest, although it may be used for longer in clinical practice. Because Naltrexone blocks the effects of opioids, it is also sometimes prescribed for extended periods for people trying to manage drug dependence.

In April 2006, the FDA approved a once-a-month injectable form of Naltrexone, which is marketed as Vivitrol, for the treatment of alcohol dependence. Several studies demonstrated the monthly injection form of Naltrexone was more effective in maintaining abstinence over the pill form because it eliminates the problem of medication compliance.

Rapid Detoxification Implant

An implant form of Naltrexone is used in a controversial process called rapid detoxification for opioid dependence. In rapid detox, you're placed under general anesthesia and a Naltrexone implant is surgically placed in your lower abdomen or posterior. This procedure is usually followed by daily doses of Naltrexone for up to 12 months.

The FDA has not approved the implant form of Naltrexone. Although the rapid detox procedure is promoted as a one-time "cure" for drug addiction, research has shown that it is really more effective as an initial step in a long-term rehabilitation process.

Side Effects

Naltrexone can cause upset stomach, nervousness, anxiety, or muscle and joint pain. Usually, these symptoms are mild and temporary, but for some people, they can be more severe and longer lasting.

In rare cases, Naltrexone causes more severe side effects including confusion, drowsiness, hallucinations, vomiting, stomach pain, skin rash, diarrhea, or blurred vision. Contact your doctor immediately if you experience any of these symptoms.

Large doses of Naltrexone can cause liver failure. You should stop taking Naltrexone immediately if you experience any of the following symptoms: excessive tiredness, unusual bleeding or bruising, loss of appetite, pain in the upper right part of the stomach, dark urine, or yellowing of the skin or eyes. Read the full list of symptoms in the warning published on the Naltrexone packaging.


Naltrexone is prescribed only after you've stopped drinking alcohol or taking opioids for seven to 10 days because it can cause serious withdrawal symptoms if it is taken while you're still using drugs.

People who have acute hepatitis, liver or kidney disease should not take Naltrexone. Patients who are using narcotic painkillers should not take it nor should anyone who is allergic to any other drugs. Women who are pregnant or breastfeeding should not take Naltrexone.

Naltrexone does not help someone stop drinking or doing drugs—it is used to help people who have already stopped maintain their abstinence. It does not treat alcohol or drug withdrawal symptoms.


Research has shown that Naltrexone can reduce craving for alcohol and drugs for some people, but it does not work for everyone. Like most pharmaceutical treatments for alcohol and drug abuse, it works best if it is used in connection with an overall treatment regime, such as psychosocial therapy, counseling, or support-group participation.

Naltrexone does not "cure" addiction, but it has helped many who suffer from alcohol or drug addiction to maintain abstinence by reducing their craving for alcohol or drugs.

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