Do you Know When the Inhaler is Empty?

To measure the ability of pediatric patients to determine if their metered dose inhaler (MDI) was empty, evaluate proper technique, and disposal of the device.

Children with asthma, preschool wheezing, bronchiectasis, or cystic fibrosis who were previously prescribed an MDI were enrolled from the West Midlands Pediatric Severe Asthma Network in the United Kingdom during routine outpatient appointments or admission to the hospital.

A prospective cross-sectional study of 147 children seen between October 2020 and September 2021 evaluated demographic data on age, sex, diagnosis, asthma attacks (where applicable), inhaler technique, and method of inhaler disposal. Families were shown an MDI inhaler that had already been actuated with the recommended 200 doses (empty inhaler). They were asked how they knew that the inhaler had medicine left in it. Those families bringing their inhalers from home were asked to comment on the number of puffs left in their MDI by reading the dose counter if the counter was present. Additional written information was given on using the inhaler, the proper technique, and knowing when the MDI is empty.

The median age of study participants was 9.5 years (interquartile range 2–15), with 75% having asthma, 12.1% preschool wheezing, 3.2% cystic fibrosis, and 9.5% bronchiectasis. Of patients, 83.5% had appropriate inhaler techniques and 92% used the correct spacer size for age.

However, only a minority (26.5%) could determine correctly that the inhaler was empty.

Incorrect methods of determining inhaler doses included shaking the inhaler (69.9%) and trying to look for visible particles after actuating (29.9%). Of the patients who had their controller inhaler with them, 18.2% were carrying inhalers with a dose counter reading of 0. Inhaler brands without a dose counter did not have any safety verbiage about determining inhaler completion. Most patients incorrectly disposed of their inhalers in the garbage (83%) instead of at their pharmacy.

Pediatric patients with inhalers were found to have a good grasp on inhaler technique and correct spacer usage. However, only a minority of the patients could determine when their MDI was empty, both with and without dose counters.

Global Initiative for Asthma and the National Heart, Lung, and Blood Insititute guidelines recommend reviewing inhaler techniques and proper use of devices and spacers at each asthma visit, but clearly, more is needed. It is easier to achieve reasonable asthma control when the inhaler is not empty. Many inhalers continue to have propellant-only doses after the active medicine is long gone. Except for counting the actuations, there is no easy way of identifying when the medicine has run out in an MDI without a dose counter. With three-quarters of patients and families unable to identify an empty MDI and one-fifth of home inhalers having empty dose counters, improvement in knowing when it is time to get more medicine is essential for asthma management in an acute flare and for daily maintenance medications. Pharmaceutical companies also need to be more responsible for providing information on when the inhaler is empty and creating inhalers with easy-to-understand dose counters. Also, with growing concerns for climate change, patients should be encouraged to properly dispose of inhalers at their local pharmacies to help lower medication carbon footprints.