Abstract

We determined whether patients with asthma or COPD could determine that their rescue medicines were empty or not, and compared metered-dose inhaler (MDI) and turbuhaler forms.

A face-to-face interview questionnaire was given to the patients who attended our Allergic Diseases and Chest Diseases clinics during May 2005-January 2006, and 190 patients answered the questionnaire.

Ninety asthmatics (47.4%) and 100 COPD patients (52.6%) were enrolled in the study. All the COPD patients used MDI for rescue medication. We found that 78 (86.7%) of asthmatics but only 24 (17.5%) of COPD patients were educated about inhaler usage (p<0.00). Of the 162 patients (83.1%) who used MDI as rescue medication, 135 (83.3%) could recognize that their medicine was empty if no drug was available when they applied pressure. As for weighing the canisters, we found that shaking the canisters before usage leads to different amounts of remnant, and hence weight of the canister after the usage depends on whether it is shaken or not. Therefore, canister depletion could not be correctly estimated by weighing. All the patients who used a turbuhaler were asthmatic and 82.1% of them could determine correctly whether their rescue medicine was empty or not.

For patients using MDI, counting the number of administered doses is the only accurate method, otherwise the turbuhaler form should be preferred. We believe that patients with asthma and COPD should be educated by their doctors about how to recognize that their rescue medicine is empty.