What Is Naltrexone?

Naltrexone is an opioid antagonist which can help people reduce or quit drinking alcohol. An opioid antagonist is a drug which blocks the effects of opiates in the brain. The brain contains natural opiates called endorphins. Naltrexone blocks both the effects of opiates like heroin and morphine as well as blocking the effects of the endorphins--the brains own naturally occurring opioids. When people drink alcohol it causes the release of endorphins in the brain. This reinforces the drinking behavior and helps to cause it to become a habit. Naltrexone blocks the reinforcing effect of the endorphins in the brain and leads to the extinction of the drinking habit.

Research by Dr. David Sinclair in Finland suggests that naltrexone is most effective if taken one hour before one intends to drink alcohol. This is known as the Sinclair method. The Sinclair method says that naltrexone should only be taken before drinking and not otherwise. This differs from the way in which naltrexone is prescribed in the US where the FDA recommends that patients take naltrexone daily and abstain from alcohol entirely.

CAUTION: Naltrexone should be avoided by people suffering from liver damage. Nausea is the most commonly reported side effect of naltrexone--10% of subjects tested reported nausea. Naltrexone is generally considered safe for the liver at recommended dosages but overdosage can cause liver damage. It is recommended that patients taking naltrexone wear a medic alert bracelet because naltrexone renders narcotic painkillers such as morphine completely ineffective. For full FDA cautions on naltrexone please click here.

For more information please see the following HAMS articles about naltrexone.

Naltrexone and the Sinclair method of pharmacological extinction

Alcohol, Naltrexone, and the Magic of Pharmacological Extinction

The Efficacy of Antabuse, Campral, and Naltrexone in Treating Alcohol Use Disorders

For more information about alcohol and naltrexone there is Roy Eskapa's book The Cure for Alcoholism: Drink Your Way Sober Without Willpower, Abstinence or Discomfort

Please also visit our web page: Medications for Abstinence or Moderate Drinking

REFERENCES:

Anton RF et al. (2006). Combined pharmacotherapies and behavioral interventions for alcohol dependence: the COMBINE study: a randomized controlled trial. JAMA. May 3;295(17):2003-17.
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Garbutt JC (2009). The state of pharmacotherapy for the treatment of alcohol dependence. Journal of Substance Abuse Treatment. Jan;36(1):S15-23.
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Heinälä P, Alho H, Kiianmaa K, Lönnqvist J, Kuoppasalmi K, Sinclair JD. (2001). Targeted use of naltrexone without prior detoxification in the treatment of alcohol dependence: a factorial double-blind, placebo-controlled trial. Journal of Clinical Psychopharmacology. Jun;21(3):287-92.
PubMed Abstract

Sinclair JD. (2001). Evidence about the use of naltrexone and for different ways of using it in the treatment of alcoholism. Alcohol and Alcoholism. Jan-Feb;36(1):2-10.
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