A randomized crossover study assessing critical errors, preferences, and ease of use of two multidose powder inhalers.

Background: The effectiveness of inhaled medications in asthma and COPD is significantly impacted by inhalation errors. Feedback mechanisms, built into the design of the inhaler might reduce the number of critical errors. This study compares critical errors, preferences, and ease of use of two dry powder inhalers, the Nexthaler, and the Turbuhaler.

Research design and methods: In this multi-center, prospective, randomized, open-label, cross-over study, the proportions of asthma and COPD patients making critical errors were compared between the Nexthaler and Turbuhaler after 4 weeks of clinical use, after having been trained for the correct use of both inhalers.

Results: Ninety and 49 patients with asthma and COPD, respectively, were assessed. No significant difference was found in the number of critical errors between the two inhalers (3 with Nexthaler and 5 with Turbuhaler). However, more patients preferred the Nexthaler (57.6%) over the Turbuhaler (34.5%) (p = 0.006), while 7.9% stated no preference.

Conclusions: The study found no significant differences in critical error rate between the Nexthaler and Turbuhaler but the Nexthaler was preferred over the Turbuhaler. This study highlights the importance of dedicating sufficient time to instructing patients on the correct inhalation technique, which can lead to long-term retention of the inhalation technique.