Twenty-year trends in pharmaceutical fentanyl and illicit fentanyl deaths, Australia 2001-2021

Background: Increasing overdose deaths attributable to illicitly manufactured fentanyl and fentanyl analogues in North America has driven international concern about the expansion of these substances into drug markets elsewhere. This paper investigates 20-year trends in fentanyl deaths in Australia, distinguishing between deaths attributable to pharmaceutical, and to illicitly manufactured fentanyl and fentanyl analogues.Methods: Analysis of fentanyl overdose deaths (2001-2021), extracted from the National Coronial Information System (NCIS).Results: 833 fentanyl-related deaths were identified, predominantly occurring among males (73%), and people with a history of injecting drug use (67%). Rates of fentanyl deaths significantly increased between 2001 and 2014 and declined between 2015 and 2021. Drug dependence remained the most significant factor in deaths among people with a history of injecting drug use (87% vs 23% without such a history), while having died by suicide was the most significant factor for those without a history of injecting drug use (20% vs 4% respectively). Three quarters (72%) of deaths were attributable to pharmaceutical fentanyl and 21% to probable pharmaceutical fentanyl, with 5% attributable to fentanyl analogues (3%) (predominantly furanylfentanyl and acetylfentanyl) and illicitly manufactured fentanyl (2%). Deaths attributable to illicitly manufactured fentanyl and fentanyl analogues occurred from 2013 onwards.Conclusion: Pharmaceutical fentanyl deaths in Australia have declined since 2015, in parallel with overall declines in pharmaceutical opioids (including fentanyl) dispensed since 2014. Deaths continue to occur among people with a history of injecting drug use and drug dependence. Deaths attributable to illicit fentanyl have emerged since 2013 but remain low in comparison to pharmaceutical fentanyl deaths.