Inhaler devices: what remains to be done?

The 1000 Years of Pharmaceutical Aerosols Conference convened posing the question; "what remains to be done?" When applying this question to the topic of inhaler devices, two hugely different perspectives could be taken. On the one hand, it could be argued that because there is an array of delivery systems available and the industry, prescribing physicians and patients alike have considerable choice, why would we believe it necessary to do anything further? On the other hand, as an industry, we are constantly reminded by our "customers" that the inhaler devices available are less than adequate, and in some cases woefully inadequate, that they are not "patient" friendly, not intuitive to use and importantly do nothing to encourage the patient to take the medication as intended and as prescribed. So, taking the second point of view as more reflective of reality--the Voice of the Customer--our starting point must be that there is still much to do in the field of inhaler devices. The purpose of this article is to outline some key basic requirements for inhaler design and perhaps to question some of the entrenched thinking that has pervaded inhaler product design for too many years.