Assessment of methadone maintenance therapy implementation and perceived barriers to treatment participation

Methadone maintenance therapy (MMT) effectiveness depends not only on the pharmacological effects of methadone but also on the quality of program implementation and service delivery. This study aimed to assess MMT implementation according to national guidelines and explore perceived barriers to treatment participation. A mixed-methods cross-sectional study was conducted from October 2022 to October 2023. The quantitative component included all eligible patients receiving MMT during the study period (n = 230), and implementation indicators included dose initiation, dose adjustment, toxicity assessment, monitoring practices, adverse-effect management, and management of missed doses. The qualitative component involved semi-structured interviews with 5 patients, two healthcare workers, and 2 facility manager. Quantitative data were analyzed descriptively, while qualitative data were analyzed using thematic analysis. The mean treatment duration was 52.2 ± 45.2 months. Overall, MMT implementation showed high compliance with national guidelines. Appropriate initial dosing, daily clinical assessment, dose adjustment, adverse-effect management, and management of missed doses exceeded 95% compliance. Toxicity assessment before dose escalation was documented in 71.7% of cases, representing the main implementation gap. No overdose or incorrect medication administration was identified. Qualitative findings revealed policy-related, facility-related, and patient-related barriers to treatment participation, including daily medication pick-up requirements, fixed operating hours, staff shortages, infrastructure limitations, employment obligations, and ongoing illicit substance use. MMT was implemented largely in accordance with national guidelines. Improving toxicity monitoring, service accessibility, staffing capacity, and operational procedures may further enhance the quality and accessibility of MMT services.