Harm reduction engagement and ongoing opioid use among adults receiving methadone or buprenorphine in Philadelphia

Opioid Use Disorder (OUD), a chronic condition with significant health and social consequences, has been intensified by synthetic opioids such as fentanyl. Although medications for OUD (MOUD) reduce mortality and improve treatment retention, many individuals continue to engage in non-prescribed opioid use while in treatment. Harm reduction services (HRSs), including syringe exchange sites, supervised injection facilities, or sites that distribute fentanyl test strips or naloxone, seek to mitigate the risks associated with substance use. This study explores engagement with harm reduction services and opioid use practices among adults receiving MOUD in Philadelphia and compares these patterns between methadone and buprenorphine recipients.

We conducted a cross-sectional survey of 116 adults receiving buprenorphine or methadone for moderate-to-severe OUD at three Philadelphia treatment sites between November 2023 and October 2024. Participants completed a RedCAP-based questionnaire assessing recent opioid use, HRS utilization and attitudes, and substance use practices. Group differences were examined using t-tests, chi-square, and Kruskal-Wallis tests.

Overall, 37% of participants reported non-prescribed opioid use in the past 6 months, most commonly via injection. Sterile injection practices varied considerably. 61% of all participants had utilized harm reduction services at least once; however, regular use was uncommon, with only 29% reporting use in the past week. HRS utilization was significantly associated with fentanyl test strip use (p = 0.002) but not with consistent sterile injection practices (p = 0.20). Compared with methadone recipients, buprenorphine recipients were more likely to report HRS utilization, feel welcomed at these sites, recommend them to others, and perceive a positive community impact (all p < 0.05). There was no observed difference in non-prescribed opioid use in the last six months between buprenorphine or methadone recipients.

Despite ongoing MOUD treatment, many patients reported continued, non-prescribed opioid use and infrequent engagement with HRS. More favorable attitudes and higher HRS utilization among buprenorphine recipients suggest that MOUD setting and structure may influence harm reduction engagement. These findings add quantitative evidence describing HRS use among MOUD populations and suggests that tailoring harm-reduction supports to these contextual factors may be an important consideration for MOUD programs.