Preference for the Diskhaler rather than the metered dose inhaler in patients with airway obstruction

A powder system, the Diskhaler inhaler (DI) has been developed to overcome the limitations of the metered dose inhaler (MDI) in the treatment of obstructive airway diseases. Seventy-three patients were enrolled in this prospective study to compare these 2 modes of treatment. The first 2 weeks involved using the DI and the second 2 weeks the MDI. We found that the Diskhaler was easy to learn to use with a success rate of 68.0% on the first attempt, and 100% by the third. Only 4.8% patients could not perform the whole procedure perfectly two weeks later, compared with a 9.5% failure rate with the MDI. The use of the DI did not result in hand-breathing coordination problems as found in 25% of MDI users. After two weeks of use, 65.6% preferred the Diskhaler (P < 0.001), 89.1% felt it was more convenient to use (P < 0.001), and 85.1% felt it was easier to carry around (P < 0.01) compared with previous devices used. Among the 52 patients who completed the study using both inhalers, more patients (92.3%) using the DI were able to use the device correctly than those using the MDI (65.4%). After 2 weeks of use, 100% of the Diskhalers were still working, and 85.0% were kept clean. The only problem encountered was that 0.2% of the blisters had not been punctured appropriately. This should be emphasized when teaching the patients. In conclusion, the Diskhaler is easier to learn, simpler to manipulate and more convenient to use resulting in an increased patient compliance. It is also environmentally a better choice for inhalation therapy.