Benzodiazepine drugs in Australia: associated mortality and morbidity

Trends in licit opioid use in Australia, 1984-1998: comparative analysis of international and jurisdictional data

OBJECTIVES

To examine trends from 1984 to 1998 in licit opioids used in Australia compared with nine other developed countries, and in New South Wales compared with other Australian jurisdictions.

DESIGN

Poisson regression analysis of annual rates of national and jurisdictional consumption of methadone, morphine and pethidine.

MAIN OUTCOME MEASURES

All drug data were standardised to defined daily doses per 1000 population per day.

RESULTS

Methadone consumption increased by, on average, 12% per year (RR, 1.12; 95% CI, 1.08-1.17), with Australia in the first rank of countries. Morphine use increased by 5% per year (RR, 1.05; 95% CI, 1.02-1.09), with Australia ranking equal second with three other countries behind Denmark. Consumption of pethidine in all 10 countries was unchanged (RR, 0.99; 95% CI, 0.97-1.00), with Australia equal first. In Australia, use of methadone syrup increased by 17% per year (RR, 1.17; 95% CI, 1.16-1.17) and by 11% per year for methadone tablets (RR, 1.11; 95% CI, 1.10-1.12). Consumption of methadone syrup in NSW was more than double that of any other jurisdiction. Consumption of methadone tablets was 2.4 times higher in South Australia (RR, 2.35; 95% CI, 2.09-2.65) than NSW. The Northern Territory, Tasmania and Queensland also had significantly higher consumption than NSW. From 1991 to 1998, controlled-release morphine consumption increased by 27% per year nationally (RR, 1.27; 95% CI, 1.24-1.30). The NT had 2.6 times more supply of morphine (RR, 2.63; 95% CI, 1.71-4.03) and Tasmania 58% more supply than NSW (RR, 1.58; 95% CI, 1.11-2.25).

CONCLUSIONS

Australia's consumption of licit opioids ranked high internationally. There were diverse trends in the supply of licit opioids to Australia's jurisdictions, resulting in a heterogeneous pattern throughout the country.

Benzodiazepine utilisation in Australia: report from a new pharmacoepidemiological database

This study surveys the total community prescription use of benzodiazepine agents in Australia for the years 1990 and 1991. Also included is information on the utilisation of these agents on the Pharmaceutical Benefits and Repatriation Pharmaceutical Benefits Schemes (PBS/RPBS) over the period 1987 to 1991. The Australian data are from the Drug Utilization Subcommittee (DUSC) database, which is derived from two sources: the PBS/RPBS (subsidized prescriptions), and a national sample of Pharmacy Guild of Australia pharmacies (private and under-copayment general prescriptions). The data are converted to defined daily doses per 1000 inhabitants per day (DDD/1000/day) in accordance with the unit of measurement for drug utilisation studies approved by the World Health Organization. Benzodiazepine utilisation was 33.96 DDD/1000/day for 1990 and 29.31 DDD/1000/day for 1991. The four drugs listed on the Pharmaceutical Benefits Scheme, namely diazepam, oxazepam, nitrazepam and temazepam, constituted 82 per cent of the Australian market. The availability of government subsidy appears to influence benzodiazepine- prescribing behaviour. Benzodiazepine utilisation has been falling in recent years. The fall may be related to the impact of new guidelines and community awareness campaigns. There are major differences in the composition of the market between Australia and the Nordic countries.