INTRODUCTION: Methadone maintenance treatment (MMT) is among the best strategies for reducing harms associated with illegal opioid use, yet it is hindered by low rates of treatment initiation and retention that limit its impact. There has been a lack of studies that describe how people who use illegal opioids use methadone–both from opioid treatment programs, and bought illegally–over time, or what factors correlate with long-term participation in MMT.
METHODS: We collected monthly survey data from N = 412 people who use illicit opioids in New York City from April 2019–2022. We used bivariate analyses to estimate the distribution of baseline sociodemographic and background characteristics. Multinomial logistic regression was then used to estimate the association between those characteristics and methadone use over time.
RESULTS: Findings show that people who are older, who used heroin for longer amounts of time, and who had multiple episodes of substance use disorder treatment other than medication for opioid use disorder are more likely to use MMT consistently over time.
DISCUSSION: Our findings may be related to the many barriers to long-term participation in MMT, such as travel distance, the need for regular attendance, and patients’ dissatisfaction with opioid treatment programs. Consistent participation in MMT may become acceptable only when the difficulties and burdens of criminalized drug use begin to outweigh those of MMT participation, and after non-medication-using treatments have already been tried. Efforts to make MMT less burdensome could reduce the tendency to avoid MMT until later in life and improve people’s consistency of participation over time.
People who use illegal opioids use of methadone over time, and what characteristics are correlated with staying in methadone maintenance treatment
Substance Use and Misuse [Epub 2025 Nov 30]. doi: 10.1080/10826084.2025.2586255.