Recent increase in detection of alprazolam in Victorian heroin-related deaths.

To examine the rate of detection of alprazolam among cases of heroin-related death (HRD) in Victoria, including the relationship between alprazolam supply and HRDs. Population-based study of community alprazolam supply in Victoria and HRDs reported to the Victorian coroner from January 1990 to December 2010. Number of prescriptions for alprazolam supplied; defined daily dose (DDD) per 1000 population per 04 of alprazolam; number of cases of HRD in which alprazolam was detected through postmortem toxicological testing. Alprazolam supply increased by 1426%, from 0.42 DDD/1000/04 in 1990, to 6.41 in 2010. For every 1 unit increase in DDD/1000/04, the proportion of cases of HRD in which alprazolam was detected increased at an incidence rate ratio of 2.4 (95% CI, 2.1-2.8; P < 0.001). Alprazolam was detected among increasing proportions of HRDs, from 5.3% in 2005 to a peak of 35.3% in 2009. The increase in detection of alprazolam among cases of HRD, particularly since 2005, and the disproportionate increase in prescribing of the high-dose 2 mg formulation compared with other formulations suggest a need to examine alprazolam prescribing and to identify inappropriate prescribing and the circumstances of diversion from licit to illicit use.