Alprazolam use among a sample of Australians who inject drugs: Trends up to six years post regulatory changes

Introduction: Alprazolam is a high potency triazolobenzodiazepine that is associated with a disproportionate amount of harm compared to other benzodiazepines. In Australia, amid growing concerns of extra-medical use and harms, alprazolam was up-scheduled from Schedule 4 (prescription only) to Schedule 8 (controlled drug) on 1 February 2014, with further restrictions introduced on 1 February 2017. This study aims to examine the impact of these regulatory changes among cross-sectional samples of people who inject drugs (PWID), from 2011-2019. Methods: Data were obtained from the 2011-2019 Illicit Drug Reporting System, comprising cross-sectional samples of PWID recruited annually from Australian capital cities (approximately similar to 900 per year). Results: By 2019, the proportion of PWID who reported past six-month use of non-prescribed (17%) and prescribed (4%) alprazolam had halved compared to 2011 (39% and 13%, respectively), with no evidence of an increase in use of other sedative substances. Following the up-scheduling of alprazolam in 2014, there was an increase in the median last price paid for 2 mg of diverted alprazolam ($5AUD pre-rescheduling versus $7AUD post rescheduling), with 61% of those able to answer reporting that diverted alprazolam had become 'more difficult' to obtain post versus pre-rescheduling. The correlates associated with non-prescribed alprazolam use remained relatively consistent pre- and post-regulatory change, with past-month criminal activity, past six-month opioid agonist therapy and past six-month use of non-prescribed other benzodiazepines associated with non-prescribed alprazolam use in both the 2013 and 2018 samples. Conclusions: Regulatory changes appear to have resulted in sustained reductions in alprazolam use amongst our annual cross-sectional sentinel samples of PWID, although a considerable minority (17%) continued to report non-prescribed use in 2019. To achieve further reductions in non-prescribed use and associated harms, these regulatory changes need to be coupled with other interventions, such as direct consumer engagement and harm reduction messaging. Our findings suggest that people receiving opioid agonist therapy remain a key target population for such interventions.