Background: Methadone is an opioid receptor agonist medication used in the treatment of opioid use disorder. It is tightly regulated by SAMHSA and must be dispensed daily under direct observation at federally certified opioid treatment programs (OTPs). Geographic distance to OTPs is thus a major barrier that people with opioid use disorder (OUD) face in accessing treatment. The purpose of this study was to examine public transit access to OTPs for methadone treatment in Miami, Florida.

Methods: Public transit times were calculated using the R library r5r, which facilitates multi-modal transportation network routing. General Transit Feed Specification data was combined with street network data from OpenStreetMap for Miami-Dade County. Transit times were estimated from the population-weighted centroid of each zip code with enrollees of the IDEA Miami Syringe Services Program (SSP) to the nearest OTP using 10 departure windows that aligned with OTP service hours.

Results: The average one-way transit time from zip codes with SSP clients in Miami-Dade County to the nearest OTP is 78 minutes. 69 of the 73 (95%) zip codes with SSP clients in Miami-Dade County have an average transit time to the closest OTP greater than 30 minutes. Transit times differ substantially between zip codes with different numbers of SSP clients, but not between departure windows.

Conclusions: To our knowledge, this study is the first to quantify public transit times to methadone treatment for people with OUD in the United States. In previous studies, ‘opioid treatment deserts’ have been defined as a public transit travel threshold of 30 minutes. Nearly all zip codes with SSP clients in Miami-Dade County can thus be classified as methadone treatment deserts. The public transit times between SSP clients’ locations in Miami-Dade County and the four registered OTPs represent a potentially insurmountable barrier to methadone treatment.