Dry powder inhaler selection in COPD: integrating device design, formulation performance, and patient inspiratory capability

INTRODUCTION: Appropriate dry powder inhaler (DPI) selection is essential for effective COPD management because pulmonary drug delivery depends on interactions between formulation properties, device design, and patient capability. This review proposes a Formulation - Device - Patient (FDP) matching framework to support individualized DPI selection. AREAS COVERED: A structured search of PubMed and Google Scholar identified publications on COPD, DPI selection, inspiratory flow, device resistance, aerosol performance, inhaler technique, usability, and formulation - device interactions. Evidence shows that DPIs differ substantially in internal resistance, inspiratory-flow requirements, dose-preparation mechanisms, aerosolization characteristics, handling complexity, and feedback systems, and therefore should not be considered interchangeable. Appropriate device selection requires assessment of inspiratory capability alongside manual dexterity, cognitive function, comorbidities, prior inhaler experience, patient preference, and inhaler technique. The review also highlights the limitations of direct cross-device comparisons and cautions against interpreting in vitro aerosol-performance metrics as indicators of clinical superiority. EXPERT OPINION: DPI selection should move beyond device-centered prescribing toward individualized formulation - device - patient matching. The proposed FDP framework provides a practical model for individualized DPI selection by integrating formulation characteristics, device engineering, and patient capability rather than relying on inspiratory flow or device characteristics alone.