Environmental impact of pressurised metered dose inhalers versus dry powder and soft mist inhalers, Melbourne 2022-2023

A Victorian retrospective pharmacy-based database search of all inpatient inhaler dispensing from 1 July 2022 to 30 June 2023 at The Royal Melbourne Hospital.
Findings:
– 9,246 inhalers were dispensed in a year, of which 79% were MDIs and accounted for 99% of the total inhaler carbon footprint
– Salbutamol MDI (51%), ipratropium MDI (12.5%) and budesonide/formoterol MDIs (8%) were the most frequently dispensed inhalers, accounting for 71.5% of total inhalers dispensed
– Tiotropium respimat (406 inhalers) and budesonide-formoterol DPI (379 inhalers) were the most frequently dispensed SMI/DPIs but accounted for only 4.39% and 4.01% of dispensed inhalers respectively
– the Carbon footprint of MDIs used for asthma and COPD at the hospital was equivalent to providing electricity to 50 homes for a year.
Conclusion: the environmental impact of inhaler choice should be considered in decision-making around prescribing