ABS TRACT Objective: Today, increasing opioid substance addiction has made implantation of subcutaneous opioid antagonists (such as naltrexone) a more popular treatment modality. In the literature, although the abdominal region is generally preferred for implantation, there is no study on the ideal location of these implants. In our study, it was aimed to evaluate and compare which of the dorsal or abdominal regions is the more ideal site for implantation, treatment compliance, surgical wound site and complications in these patient groups. Material and Methods: For this purpose, 181 patients who were referred to us by the psychiatry department in our clinic for subcutaneous implant placement for the treatment of opioid addiction between 2016 and 2019 were included in the study. Demographic characteristics, how many times and in which areas implantation was performed, whether the patients discontinued the treatment, if they did, the reasons for discontinuation, presence of signs of infection, implant extrusion, and secondary interventions were examined. Results: Subcutaneous naltrexone implant was placed in the back region in 95 patients and in the abdominal region in 86 patients. Based on the area where the implants were placed, the patients were evaluated in terms of parameters such as compliance to treatment, infection, secondary procedure requirement, and implant extrusion in the postoperative period. It was determined that patients with implants in the back area adapted better to the treatment, required fewer secondary procedures, and experienced less infection and implant extrusion. Conclusion: In the light of these findings, in cases where subcutaneous implantation is planned for the treatment of opioid addiction, the back region is a more ideal area for implantation compared to the abdominal region.