A study of 16 deaths associated with toxic concentrations of benzodiazepines during the period of 5 years leading up to July 1994 is presented. Cases where other drugs, including ethanol, had contributed to the death were excluded. All cases were subject to a full macroscopic and microscopic examination by pathologists, and all cases were subject to a full toxicological work-up. Preexisting natural disease was a feature of 11 cases. In the remaining five cases, death was caused solely by benzodiazepines. There were 14 suicides. Nitrazepam and temazepam were the most prevalent drugs detected, followed by oxazepam and flunitrazepam. Minimum toxic femoral blood concentrations of 7-aminonitrazepam, 7-aminoflunitrazepam, and oxazepam were estimated as 0.5, 0.2, and 2 mg/L, respectively. Relating these deaths to prescription rates in Victoria suggest that flunitrazepam may be inherently more toxic if misused than other benzodiazepines currently available on the Australian market.
From the Department of Forensic Medicine, Victorian Institute of Forensic Medicine, Monash University, Southbank, Australia.
Received February 27, 1995; revision received June 20, 1995; accepted July 13, 1995.
Address correspondence and reprint requests to Dr. Olaf H. Drummer, Department of Forensic Medicine, Victorian Institute of Forensic Pathology, Monash University, 57-83 Kavanagh St., Southbank, Australia 3006.