Prescription of opioid analgesics and related harms in Australia

Abstract

Objective: To document trends in: (i) prescribing of morphine and oxycodone; (ii) hospital separations for overdose; (iii) presentations for treatment of problems associated with these drugs; and (iv) oxycodone-related mortality data in Australia.

Design and setting: Cross-sectional study analysing prescriptions for morphine and oxycodone based on figures adjusted using Australian Bureau of Statistics estimated resident population and prospectively collected data from: (i) the National Hospital Morbidity Database on hospital separations primarily attributed to poisoning with opioids other than heroin ("other opioids"); (ii) the Alcohol and Other Drug Treatment National Minimum Data Set for treatment episodes where morphine or oxycodone were the primary or other drugs of concern; (iii) the National Coronial Information System on deaths where oxycodone was the underlying cause of death or a contributory factor.

Main outcome measures: Population-adjusted numbers of (i) prescriptions for morphine and oxycodone by 10-year age group, (ii) hospital separations for "other opioid" poisoning, and (iii) treatment episodes related to morphine or oxycodone; and (iv) number of oxycodone-related deaths.

Results: Prescriptions for morphine declined, while those for oxycodone increased. Prescriptions for both were highest among older Australians. Hospital separations for "other opioid" poisoning doubled between the financial years 2005-06 and 2006-07. Treatment episodes for morphine remained stable, while those for oxycodone increased. There were 465 oxycodone-related deaths recorded during 2001-2009.

Conclusions: Oxycodone prescriptions in Australia have increased, particularly among older Australians. The increase may, in part, reflect appropriate prescribing for pain among an ageing population. However we are unable to differentiate non-medical use from appropriate prescribing from this data. In comparison to heroin, the morbidity and mortality associated with oxycodone is relatively low in Australia. There is a continued need for comprehensive training of general practitioners in assessing patients with chronic non-malignant pain and prescribing of opioids for these patients, to minimise the potential for harms associated with use of these medications.