Fentanyl use among street drug users in Toronto, Canada: behavioural dynamics and public health implications.

Prescription opioids (POs) are playing an increasingly central role in street drug use and related harms in North America. One distinct PO substance of interest is Fentanyl (Duragesic), a potent opioid analgesic designed for transdermal time-release application. Studies from Europe and North America have documented the sizeable overdose and mortality burden associated with the non-medical use of this drug. This study explores practices and risk dynamics associated with Fentanyl abuse, also considering public health implications. Semi-structured interviews were conducted with 25 regular street-entrenched illicit PO users in Toronto, Canada, a sub-sample of which were recent Fentanyl users. Results showed that while relatively rare on the illicit PO market in Toronto, Fentanyl is a highly desired, sought after and relatively expensive PO drug among street users. In addition, the new 'matrix' patch technology implemented for Fentanyl since 2005 is a limited safeguard against abuse as simple extraction methods are utilized by street users. Finally, distinct risk behaviours relevant for public health emerge due to the high black market costs of Fentanyl and the extraction techniques applied, potentially facilitating high risks for infectious disease (e.g., HCV, HIV) transmission and/or overdose. Consequently, prevalence and practices of Fentanyl use by street users require closer monitoring, targeted interventions and further research regarding risks and outcomes.