Inhaler devices play an important role in the management of obstructive lung diseases including asthma, chronic obstructive pulmonary disease (COPD), and asthma–COPD overlap. Some of these patients show suboptimal inhaler techniques; however, time for inhaler instruction by pharmacists is limited in daily clinical practice. Therefore, sufficient education regarding inhaler device handling should be provided within a limited time frame. The current study aimed to investigate the instruction methods provided by community pharmacists and their influence on inhaler device handling techniques in outpatient clinical care settings. We retrospectively collected the data of outpatients with obstructive lung diseases who were referred to our hospital and who underwent inhalation technique assessments conducted by community pharmacists. The prevalence of handling errors, clinical characteristics of patients, and instruction methods were analyzed. In total, 138 patients (170 devices) were included in this study. Approximately 70.0% of patients received verbal explanations combined with leaflets about inhaler instructions. In a device-based analysis, 63 (37.1%) of 170 devices had at least one technical error and 18 (10.6%) of the devices had critical errors. Patients without critical errors received practical demonstration instructions from pharmacists combined with leaflets and verbal explanations more frequently than those with critical errors (22.8 vs. 0%, p < 0.01). This study revealed that patients with obstructive lung diseases commonly present with inhaler device handling errors and critical errors were observed with non-negligible frequency in daily practice in Japan. Combined instruction with leaflet, verbal explanation, and pharmacist demonstration may be effective in improving proper inhaler treatment.
