Open label trial of naltrexone implants: measuring blood serum levels of naltrexone

The usefulness of oral naltrexone has been limited by compliance. Sub-cutaneous implants would seem to offer a solution to this problem and improve long-term outcomes. The aim of the present study was to compare levels of blood serum naltrexone of patients who had received a naltrexone implant after detoxification to a number of dependent variables of interest. These dependent variables included drug use including urine screens of each patient, any adverse response to the implant, subjective evaluation of self-esteem, quality of relationships, and changes in social functioning. Sixty six patients received an implant and were surveyed; urine and blood samples were taken at about 1, 3, and 6 months after implantation. Naltrexone levels were on average above 1 ng/mL at 6 months after insertion and patients showed significant improvements on all dependent variables. The preliminary evidence indicates that implants can improve compliance rates and outcomes.