This study assessed whether naltrexone, an opioid antagonist, might be effective in reducing excessive gambling behavior in people who also drink heavily. The efficacy of naltrexone was evaluated in a randomized, double-blind, placebo-controlled trial. Fifty-two subjects who had significant problems with both gambling and alcohol received 11 weeks of either naltrexone or placebo.

With the growing popularity of gambling, there has been an increase in the number of individuals with problem gambling. As we learn more about the way we can help problem gamblers, there is a great interest developing effective medications for this problem. Although there is much to learn about the factors that lead to gambling problems, there is some research showing that one of the reasons why gambling may be so rewarding and difficult to stop is due to the release of endogenous opioids, a specific brain chemical that is associated with the feeling of pleasure. It is possible that medications known to affect the opioidergic neurotransmitter system which produces endogenous opioids may be beneficial in reducing pathological gambling. One such medication is naltrexone, an opioid antagonist, that has been shown to be effective in reducing alcohol consumption and approved for use in the treatment of alcohol dependence. This study assessed whether naltrexone might be effective in reducing excessive gambling behavior in people who also drink heavily. The efficacy of naltrexone was evaluated in a randomized, double-blind, placebo-controlled trial. Fifty-two subjects who had significant problems with both gambling and alcohol received 11 weeks of either naltrexone or placebo. Everyone also received 7 weeks of cognitive-behavioral counselling to help them reduce or stop drinking and gambling. Changes in alcohol and gambling behavior were measured at the beginning of treatment, at the end-of-treatment and 3, 6 and 12-months after treatment follow-up. The results showed that there were no significant differences between those who received placebo versus those who received naltrexone on any alcohol or gambling measure (i.e., frequency of drinking/ gambling, amount of drinking/ gambling, money spent of gambling, urges to drink/ gamble). However, treatment in general was effective as everyone, regardless of the treatment they received, were gambling and drinking significantly less at the end-of-treatment and during the year follow-up. The conclusion of the study was that naltrexone was not an effective treatment for concurrent alcohol use and gambling problems.

Inclusion Criteria:

• DSM-IV diagnosis of alcohol abuse and dependence
• Diagnosis of pathological gambling
• Drinking on at least 50% of the days in the preceding month
• Gambling at least weekly in the month prior to assessment

Exclusion Criteria:

• Dependence or abuse of any other psychoactive substances (except for nicotine dependence)
• Concurrent diagnoses of any other psychiatric disorder,
• Serious medical illness
• Laboratory evidence of significant hepatocellular injury
• Use of disulfiramuse and/or opioid-containing medications
• Psychosocial crisis
• Pregnancy
• Inability to read or write English.
• Poor motivation to change alcohol or gambling behavior