Australian Polypharmacy Trends Between 2013 and 2024: A Repeated Cross-Sectional Study in the Adult Population

Abstract

The aim of this repeated cross-sectional study was to estimate polypharmacy prevalence and trends in Australian adults between 2013 and 2024. Dispensing records of medicines subsidised by the Australian Pharmaceutical Benefits Scheme (PBS) were analysed for a nationally representative 10% sample of PBS-eligible beneficiaries. The outcomes for this study were annual polypharmacy and hyperpolypharmacy prevalence, defined as ≥5 and ≥10 regular medicines, respectively, and average annual percentage change (AAPC), overall and by gender-stratified age groups. These groups are defined broadly as adult (18–64 years) and older adult (≥65 years), and as younger adulthood (18–39 years), middle (40–64 years), early older (65–84 years) and later older (85+ years) age. Polypharmacy prevalence rose from 8.0% in 2013 to 9.2% (AAPC+1.4%), with two million Australians exposed in 2024. Although prevalence was initially higher among women, by 2024 men had surpassed women from middle age onward. Increasing AAPC was observed among adult and older adult men (+1.0%, +1.3%), while remaining stable among women. Finer age strata showed growth among men in middle, early older, and later older age (+1.7%, +1.0%, +3.4%) and divergent trends among women, with increases in younger adulthood (+1.8%) and declines in early older age (− 0.7%). Shifting gender trends appear driven by stabilising or declining prevalence among women alongside sustained growth among men. By 2024, men exceeded women from middle age onward, suggesting a changing prescribing landscape. These patterns highlight the need for targeted interventions, and gender-stratified monitoring to ensure prescribing is appropriate. The long-term consequences of increasing polypharmacy in younger and middle-aged adults remain unclear and warrant further investigation. Polypharmacy is to take five or more medicines at the same time. Older adults often manage an increasing number of health conditions with polypharmacy. However, the more medicines we use, the more health conditions we have and the older we are, the more likely we are to experience harmful side effects or continue using medicines that are no longer safe or necessary. This study looked at how common polypharmacy was in Australia from 2013 to 2024 and whether it changed over time across different age groups and between men and women. In 2024 polypharmacy peaked with nearly two million Australians exposed, up from 1.4 million in 2013. Over the study period, we found the proportion of older men with polypharmacy increased, while the proportion of women with polypharmacy either remained consistent or declined. Polypharmacy also increased among younger and middle-aged adults, who are not often thought of as at risk of harm from the medicines they use. These findings can help improve how medicines are prescribed by encouraging safer and more careful use, especially for older men, who are increasingly exposed to polypharmacy and the potential for medicine-related harm, and for younger people who may need support earlier in life to avoid problems as they move into older age.