Opioid Overdose Deaths with Buprenorphine Detected in Postmortem Toxicology: a Retrospective Analysis.

BACKGROUND: Buprenorphine is a unique µ-opioid receptor partial agonist with avid receptor binding, nominal euphoric reward, and a ceiling effect on sedation and respiratory depression. Despite a pharmacologic profile that enhances safety, cases of fatal opioid overdose with buprenorphine on postmortem toxicology are reported, but details of these cases in the literature are limited. METHODS: A retrospective review of opioid-involved drug overdose fatalities in Rhode Island (RI) from 2016 to 2018 using the RI Department of Health State Unintentional Drug Overdose Reporting System (SUDORS) database. Deaths with buprenorphine on toxicology testing versus opioid-involved overdose deaths without buprenorphine were compared to assess the type and number of co-exposures. RESULTS: Of 534 opioid-involved deaths, 29 (5.4%) included buprenorphine and/or norbuprenorphine on toxicology. Most frequent co-exposures are as follows: fentanyl (75.9%), norfentanyl (72.4%), cocaine (41.4%), benzoylecgonine (41.4%), cannabinoids (31.0%), ethanol (31.0%), levamisole (31.0%), and free morphine (31.0%). An average number of co-exposures for fatalities with buprenorphine were 9.24 versus 6.68 in those without buprenorphine. In one case buprenorphine was the only drug listed to cause death; all other fatalities with buprenorphine on toxicology reported additional drugs contributing to death. CONCLUSION: Decedents with buprenorphine detected on toxicology testing commonly had documented polysubstance use. Although data are limited, buprenorphine may provide some risk mitigation against full agonist opioid overdose including fentanyl. Further work should explore the use of postmortem concentrations of buprenorphine, norbuprenorphine, and other opioid metabolites to determine the role of buprenorphine in fatal overdose pharmacology.

'It's our safe sanctuary': Experiences of using an unsanctioned overdose prevention site in Toronto, Ontario.

BACKGROUND: Overdose prevention sites (OPSs) are spaces where people can consume drugs under the supervision of trained volunteers or staff and receive help in the event of an overdose. Unsanctioned OPSs are a grassroots response to the current opioid crisis in Canada. METHODS: We used rapid evaluation methods to study the experiences of 30 individuals accessing the smoking and injection services at the first unsanctioned OPS in Toronto, Ontario using semi-structured interviews. Data were analyzed using an applied thematic analysis approach to identify emergent themes related to service user experiences, characteristics of the risk environment, and recommended changes to the service model. RESULTS: The OPS represented a safe sanctuary and brought a sense of belonging to a community that often experiences discrimination. Valued aspects included: shelter; protection from violence; safety from overdoses; free equipment; information about health and social services; food and beverages; and socializing and connecting with others. Integrating peer workers in the design and delivery of services encouraged service users to visit the site. The OPS changed the risk environment by: providing access to the first supervised smoking service in Toronto; having few explicit rules and a communal approach to making new rules; allowing assisted injection, and negotiating with police to allow people to access the site with minimal contact. Service users noted the need to ensure a safe space for women and recommended extended hours of operation and moving to a more permanent space with heat and lighting for both smoking and injecting drugs. CONCLUSION: The unsanctioned OPS in Toronto served an important role in defining new, community-led, flexible responses to opioid overdose-related deaths at a time of markedly increasing mortality. Providing harm reduction services in diverse settings and expanding services to include smoking and assisted injection may increase access for marginalized people who use drugs.