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Moving from CFC aerosol to HFA aerosol or dry powder inhalers: what do patients think?
Thomas K Hartung1, Helen Allbutt, Maria Dewar
1Respiratory Department, Ninewells Hospital, Dundee, UK. Thomas.Hartung@tuht.scot.nhs.uk
Background/Objectives:
Environmentally friendly hydrofluoroalkane (HFA) pressurised metered-dose inhalers are currently being marketed to replace chlorofluorocarbon (CFC)-driven devices. It is uncertain whether these new formulations with different properties are acceptable to patients. Similarly, switching a patient to a dry powder inhaler (DPI) carries the risk of non-acceptance.
Methods:
One hundred patients with obstructive airway disease on regular CFC aerosol inhaler medication underwent a standardised, structured interview. During the interview patients were asked to use a new HFA aerosol inhaler and three DPIs in random order. Patients' notions were recorded.
Results:
Most patients (96) agreed to change from their CFC to the HFA inhaler, of those, only 12 did so with some reservation. Properties (taste, user-friendliness, design) of the HFA inhaler were rated favourably. DPIs represented an acceptable alternative to aerosol inhalers. In fact, 57 patients preferred a DPI over the HFA inhaler. Not all powder devices were equally acceptable. Replacing the CFC inhaler with patients' preferred alternative devices resulted in a more than 3-fold increase in costs.
Conclusion:
Concerns about the acceptability of reformulated CFC-free aerosol inhalers are ill founded. However, if given the choice, many patients prefer a DPI over the HFA inhaler. The transition offers an opportunity to review patients' current treatment and the proficiency of their inhaling technique. Moving to CFC-free inhalers will have revenue implications.
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