Drop in opioid use in Australia offset by spike in private scripts

Australia’s use of prescription opioid analgesics, such as oxycodone, morphine, or tramadol, dropped by 21% between 2015 and 2022, despite a substantial increase in private scripts in the same period, according to new research published in the International Journal of Drug Policy.

The downward trend was driven by a 33% reduction in Pharmaceutical Benefits Scheme (PBS) dispensing claims for opioid analgesics—mainly long-acting formulations—in light of government measures to curb use.

But about a quarter of this reduction was offset by a 55% jump in private market use of opioids outside of the PBS, say researchers from the National Drug & Alcohol Research Center (NDARC) and the Medicines Intelligence Center of Research Excellence, UNSW Sydney.

“While Australia has reduced its overall consumption of opioid analgesics, our findings indicate a significant rise in private prescriptions, which come with higher out-of-pocket costs for people in pain,” said first author and pharmacoepidemiologist, Kendal Chidwick.

“Reasons for the increase in private market use may include accessing opioids that are not subsidized under the PBS, or efforts to avoid the PBS restrictions altogether.”

In recent years, Australia has adopted a range of measures to reduce opioid use—such as introducing smaller pack sizes, restrictions on repeat scripts, and real-time prescription monitoring—with the aim of halving opioid-related harms over the five years to 2025.

Government data show that use of PBS-subsidized opioid analgesics has been declining since 2018; however, these statistics do not capture private scripts or medicines supplied to public hospital inpatients.

To get a clearer picture of population-level trends in prescription opioid use, the researchers used data from IQVIA Inc, which collects information on medicine sales to pharmacies, hospitals and other health care settings by pharmaceutical wholesalers and manufacturers.

Senior author and NDARC Research Director, Scientia Professor Louisa Degenhardt said the study provides “critical information to support quality use of these prescription medicines and reduce patient harms.”

“Combining multiple data sources helped us to shine a light on trends in private dispensing of opioids, where the patient pays the full cost without subsidy—information that is not captured in standard PBS datasets,” Professor Degenhardt said.

The analysis is also the first to show that tapentadol has replaced oxycodone as the most commonly prescribed opioid in Australia.

“Preferencing tapentadol for postoperative pain, due to perceived benefits, may be contributing to its increasing use despite limited evidence on the comparative safety of tapentadol and oxycodone post-surgery,” Chidwick said.

But she added that the number of Australians initiating PBS-subsidized tapentadol had been reducing and “may stabilize as the market matures.”

A limitation of the study was the reliance on medicine sales information to gauge private market use, which does not indicate individual patterns of use.

Provided by
National Drug and Alcohol Research Centre (NDARC)