Background: Climate change is one of the greatest public health challenges of our time. Mitigation of climate change is a challenge for all sectors of society, including the health sector. The Australian health system is responsible for 7% of Australia’s carbon footprint, with pharmaceuticals being a key contributor. The hydrofluoroalkane propellant gases in metered dose inhalers (MDIs) are potent greenhouse gases, and a shift to dry powder inhalers has been promoted in international guidelines as an important way to reduce climate impacts of prescribing.
Method: Estimation of carbon-dioxide-equivalent pollution from metered dose inhalers in the Australian health system using publicly available Pharmaceutical Benefits Schedule (PBS) data from 2019. These were multiplied by average per-canister propellant content and the accepted global warming potential of the propellant gases.
Results: Our estimate of carbon-dioxide-equivalent pollution from PBS dispensing of MDIs is 113175 tonnes for the 2019 calendar year. This is equivalent to the pollution from more than 24,000 passenger vehicles per year.
Discussion: A serious limitation is that our estimate includes only dispensed medicines tracked by the PBS. It does not include over-the-counter, privately dispensed and public hospital inhalers.
Implications for practice: MDIs remain important tools for respiratory drug delivery for many patients, especially younger children. However, for many adult patients, a shift to dry powder inhalers would achieve equivalent respiratory disease control while helping to mitigate the health system’s climate impact. In our presentation, we will put this issue into the context of the overall problem of climate change. We will keep the session practical for Australian GPs, discussing how to weigh environmental impact alongside many other important factors when selecting appropriate inhaler devices.