Although naltrexone, an opiate-receptor antagonist, has been approved by the Food and Drug Administration for the treatment of alcohol dependence, its efficacy is uncertain.

We conducted a multicenter, double-blind, placebo-controlled evaluation of naltrexone as an adjunct to standardized psychosocial treatment. We randomly assigned 627 veterans (almost all men) with chronic, severe alcohol dependence to 12 months of naltrexone (50 mg once daily), 3 months of naltrexone followed by 9 months of placebo, or 12 months of placebo. All patients were offered individual counseling and programs to improve their compliance with study medication and were encouraged to attend Alcoholics Anonymous meetings.

There were 209 patients in each group; all had been sober for at least five days before randomization. At 13 weeks, we found no significant difference in the number of days to relapse between patients in the two naltrexone groups (mean, 72.3 days) and the placebo group (mean, 62.4 days; 95 percent confidence interval for the difference between groups, –3.0 to 22.8). At 52 weeks, there were no significant differences among the three groups in the percentage of days on which drinking occurred and the number of drinks per drinking day.

Our findings do not support the use of naltrexone for the treatment of men with chronic, severe alcohol dependence.