Introduction: Medicines should have a neutral effect on the environment and delivered by devices with lower environmental impact. Changing inhalers for non-clinical reasons in COPD and asthma can lead to low adherence to treatment and/or misuse of the device, limiting clinical benefits, increasing the risk of exacerbations and, therefore, the use of healthcare resources. Within the so-called Planetary Medicine, we aimed to determine the economic and environmental impact of changing inhalers for non-clinical reasons in patients with COPD and asthma in Spain.

Methods: We searched the latest epidemiological evidence on the burden of COPD and asthma in Spain. The burden and costs from indirect inhaler changes was estimated. The carbon footprint of the procedures derived from both diseases was also estimated in metric tons of CO2 equivalent (TEqCO2).

Results: It is estimated that the total direct cost of primary and hospital care each year in Spain is ?2,405,952,187 for COPD and ?1,317,508,666 for asthma. Given that 9% of exacerbations and their consequences are due to uncontrolled changes, the estimated annual cost is of more than ?216M for COPD and ?112M for asthma. The impact of these exacerbations is 210,069 TEqCO2 for COPD and 186,681 TEqCO2 for asthma. Training patients with the change of device would cost around ?15M and would generate an additional impact of 8 million TEqCO2 on the rate of carbon emissions.

Conclusions: The change of inhalers for non-clinical reasons and the consequent lack of adherence to treatment produces is associated with a great increase in costs and a great impact on carbon emissions in Spain.