To evaluate the efficacy of naltrexone maintenance treatment in preventing relapse in opioid addicts after detoxification.
A systematic review according to the methodology developed by the Cochrane Collaboration based on either randomized controlled trials (RCTs) or controlled clinical trials (CCTs).
Seven hundred and seven heroin dependent in- and out-patients, or former heroin addicts dependent on methadone and participating in a naltrexone treatment programme; 89% were male.
Maintenance treatments on opiate dependent people after detoxification, comparing naltrexone with placebo, pharmacological or behavioural treatments.
The outcomes considered were successfully completed treatment, opioid use under treatment (re)-incarcerations during the study period, mean duration of treatment.
The outcomes tended to be slightly although not significantly in favour of the naltrexone groups. Use of naltrexone in addition to behavioural treatment significantly decreased the probability of (re-)incarceration (OR=0.30; 95% CI 0.12, 0.76). The difficulties in producing a quantitative analysis were due mainly to the heterogeneity of the included studies.
From the available clinical trials performed up to this time, there is insufficient evidence to justify the use of naltrexone in maintenance treatment of opioid addicts.