Introduction: Physicians are being encouraged to favor dry powder inhalers (DPI) over pressurized metered dose inhalers (pMDI) on environmental grounds. The EU is reviewing the F-gas regulation to accelerate emission cut-down targets (EU Climate Action).

Aims and objectives:Thoughtful use of inhalers can reduce emissions while promoting positive clinical outcomes. We aim to describe the trends of pMDI and DPI use and associated carbon footprint in Europe.

Methods:DPI and pMDI sales data between 2011?2021 were extracted from IQVIA MIDAS Quarterly 2022 and reported as total sold doses in Europe by country (Germany, France, Spain, Italy, Poland, Norway, Sweden, Finland, Denmark, and the UK). Carbon footprint calculations were based on the Medical and Chemicals Technical Options Committee 2018 assessment report.

Results: Between 2011 and 2021 the carbon footprint of inhalation therapy increased from 3.37 Mt to 3.89 Mt CO2e as a result of a 40% increase in the number of sold doses of pMDI and a 10% decrease of DPIs during this period. Replacing pMDIs with DPIs would have produced 92% fewer emissions. In 2021, emissions associated with short acting beta-2 agonists (SABA) were 1.64 Mt CO2e (41% of all emissions), 94% from pMDIs. The UK was the largest source of pMDI-related emissions in 2021 with 1.24 Mt CO2e (31% of all emissions).

Conclusions: The carbon footprint of inhaler therapy in Europe grew due to an increased use of pMDI and decreased use of DPI in many European countries. Greater focus on guideline-based controller therapy and prioritizing DPIs when clinically appropriate will potentially improve patient outcomes and lower the large greenhouse gas emissions from SABA over-reliance.