Oral inhalation therapy: meeting the challenge of developing more patient-appropriate devices

Abstract

Although oral inhalers have been mass produced for more than 50 years, there is a large body of literature in which evidence has been provided that patients either misuse their inhalers inadvertently or deliberately, thereby reducing their intended efficacy or, in the worst cases, rendering them altogether ineffective. In general, inhalers are becoming increasingly complicated with the incorporation of add-on devices, miniaturized electronics and ever more complex mechanical systems that aid aerosol delivery to the lower respiratory tract and, at the same time provide user feedback. However, these benefits often come at a significant cost, and there are signs that increasing attention will need to be given to the cost–benefit equation in the future. This review explores the development of pressurized metered-dose inhalers, dry powder inhalers and devices for liquid-droplet dispersal and inhalation from the perspective of the patient, by focusing on aspects that improve user interaction. These include designed-in features, such as breath-enhanced or breath-actuated operation that interact with the breathing pattern of the user, as well as more direct feedback aids that confirm, to the patient or healthcare provider that the dose has been delivered and that the patient has inhaled.

Keywords::

• dry powder inhaler
• feedback
• holding chamber
• metered-dose inhaler
• metered liquid inhaler
• nebulizer
• patient
• patient interface
• spacer

Acknowledgements

The authors wish to acknowledge the support of colleagues at Trudell Medical International, who have provided particular insights during the development of this overview, in particular, Kelly Armstrong and Bryan Finlay.

Financial & competing interests disclosure

The authors are full time employees of Trudell Medical International, Canada, the manufacturer of some of the devices described in this article. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.