Objective: The majority of drug addicts are polydrug dependent, and no effective pharmacological treatment is currently available for them. The authors studied the overall real-world effectiveness of naltrexone implant in this patient population.
Method: The authors assessed the effectiveness of a naltrexone implant in the treatment of coexisting heroin and amphetamine polydrug dependence in 100 heroin- and amphetamine-dependent outpatients in a 10-week randomized, double-blind, placebo-controlled trial. The main outcome measures were retention in the study, proportion of drug-free urine samples, and improvement score on the Clinical Global Impressions Scale (CGI). Analyses were conducted in an intent-to-treat model.
Results: At week 10, the retention rate was 52% for patients who received a naltrexone implant and 28% for those who received a placebo implant; the proportions of drug-free urine samples were 38% and 16%, respectively, for the two groups. On the CGI improvement item, 56% of the patients in the naltrexone group showed much or very much improvement, compared with 14% of those in the placebo group (number needed to treat=3).
Conclusions: Naltrexone implants resulted in higher retention in the study, decreased heroin and amphetamine use, and improved clinical condition for patients, thus providing the first evidence of an effective pharmacological treatment for this type of polydrug dependence.