Naltrexone blocks opioid receptors that are involved in the rewarding effects of drinking and the craving for alcohol. It has been shown to reduce relapse to problem drinking in some patients. An extended release version, Vivitrol—administered once a month by injection—is also FDA-approved for treating alcoholism, and may offer benefits regarding compliance.
Acamprosate (Campral®) acts on the gamma-aminobutyric acid (GABA) and glutamate neurotransmitter systems and is thought to reduce symptoms of protracted withdrawal, such as insomnia, anxiety, restlessness, and dysphoria. Acamprosate has been shown to help dependent drinkers maintain abstinence for several weeks to months, and it may be more effective in patients with severe dependence.
Disulfiram (Antabuse®) interferes with degradation of alcohol, resulting in the accumulation of acetaldehyde, which, in turn, produces a very unpleasant reaction that includes flushing, nausea, and plapitations if a person drinks alcohol. The utility and effectiveness of disulfiram are considered limited because compliance is generally poor. However, among patients who are highly motivated, disulfiram can be effective, and some patients use it episodically for high-risk situations, such as social occasions where alcohol is present. It can also be administered in a monitored fashion, such as in a clinic or by a spouse, improving its efficacy.
Topiramate is thought to work by increasing inhibitory (GABA) neurotransmission and reducing stimulatory (glutamate) neurotransmission, although its precise mechanism of action is not known. Although topiramate has not yet received FDA approval for treating alcohol addiction, it is sometimes used off-label for this purpose. Topiramate has been shown in studies to significantly improve multiple drinking outcomes, compared with a placebo.
Combined With Behavioral Treatment
While a number of behavioral treatments have been shown to be effective in the treatment of alcohol addiction, it does not appear that an additive effect exists between behavioral treatments and pharmacotherapy. Studies have shown that just getting help is one of the most important factors in treating alcohol addiction; the precise type of treatment received is not as important.
Anton, R.F.; O’Malley, S.S.; Ciraulo, D.A.; Cisler, R.A.; Couper, D.; Donovan, D.M.; Gastfriend, D.R.; Hosking, J.D.; Johnson, B.A.; LoCastro, J.S.; Longabaugh, R.; Mason, B.J.; Mattson, M.E.; Miller, W.R.; Pettinati, H.M.; Randall, C.L.; Swift, R.; Weiss, R.D.; Williams, L.D.; and Zweben, A., for the COMBINE Study Research Group. Combined pharmacotherapies and behavioral interventions for alcohol dependence: The COMBINE study: A randomized controlled trial. The Journal of the American Medical Association 295(17):2003–2017, 2006.
National Institute on Alcohol Abuse and Alcoholism. Helping Patients Who Drink Too Much: A Clinician’s Guide, Updated 2005 Edition. Bethesda, MD: NIAAA, updated 2005. Available at pubs.niaaa.nih.gov/publications/Practitioner/CliniciansGuide2005/clinicians_guide.htm