Abstract

Context
Pressurised metered-dose inhalers (pMDIs) are widely used in asthma and COPD management, yet dosing errors remain under-recognised. Two prevalent issues are: (1) disposal of inhalers with substantial doses remaining, and (2) continued use after depletion[1]—both negatively impacting disease control and contributing to waste.

Problem
Despite national guidelines and awareness campaigns, there is limited real-world evidence quantifying the scale of these errors in community settings or evaluating the role of pharmacists in addressing them. This pilot aimed to identify MDI dosing errors and assess the feasibility of pharmacist-led interventions using digital tools.

Strategy for Change
Six branches of the Pearl Chemist Group in South West London were equipped with calibrated digital scales, enabling pharmacy staff to assess residual doses in returned MDIs. Patients were offered Smart MDI Sensors—electronic tracking devices—to support real-time inhaler dose monitoring. The intervention also included brief patient education on correct inhaler use and safe disposal practices.

Measurement of Improvement
Key data points included:
- Frequency and extent of residual doses in returned inhalers
- Uptake and usage rates of Smart MDI Sensors
- Patient satisfaction and behavioural changes regarding inhaler use

Results
- High incidence of dosing errors was confirmed, aligning with prior national findings[2]
- Most patients accepted the electronic monitors when offered at no cost
- A significant proportion indicated willingness to purchase the devices themselves
- Regular use of the devices was reported, with improved patient confidence in dose tracking
- Pharmacists observed increased engagement and higher rates of inhaler returns for disposal
Lessons Learned
Community pharmacies are well-placed to deliver low-cost, high-impact interventions for inhaler optimisation. Staff engagement and patient communication were key enablers. Digital solutions were not only accepted but valued by patients, indicating scalability.

Message for Others
This pilot demonstrates a replicable, pharmacist-led model to address MDI dosing errors using digital adherence tools. Plans are underway to pilot a broader MDI Optimisation Service with national applicability. Interested pharmacists are invited to participate.

References
1. Beckett R, Estimating remaining doses in a salbutamol pMDI via canister weight.
2. Murphy A, How do patients determine when their inhaler is empty?