Long-term effects of pharmacotherapy on relapse prevention in alcohol dependence

There is growing evidence that pharmacological treatment with two of the best validated anticraving drugs, acamprosate and naltrexone, is efficacious in promoting abstinence in recently detoxified alcohol-dependent subjects.

The stability of effects after termination of treatment remains to be answered, especially when combining both the drugs.

After detoxification, 160 alcohol-dependent subjects participated in a randomized, double-blind, placebo-controlled trial. Patients received naltrexone or acamprosate or a combination of naltrexone and acamprosate or placebo for 12 weeks. Patients were assessed weekly by interview, self-report, questionnaires and laboratory screening. Additionally, follow-up evaluation based on telephone interview of participants, general practitioners and relatives was conducted 12 weeks after terminating the medication.

At week 12, the proportion of subjects relapsing to heavy drinking was significantly lower in the group with combined medication compared with both placebo and acamprosate (P < 0.05). No difference was detectable between acamprosate and naltrexone, both of which were superior to placebo (P < 0.05). Relapse rates were 28% (combined medication), 35% (naltrexone), 50% (acamprosate) and 75% (placebo). After follow-up (week 24), combined medication led to relapse rates significantly lower than placebo, but not lower than acamprosate. Again, both naltrexone and acamprosate were superior to placebo. Relapse rates were 80% (placebo), 54% (acamprosate), 53% (naltrexone) and 34% (combined medication).

The results of this study highlight the stability of effects of pharmacotherapy on relapse prevention in alcohol dependence.