Pulmo Scale Universal Dose Counter For Metered Dose Inhalers
PATIENT’S ABILITY TO DETERMINE WHEN TO REPLENISH THEIR INHALERS (pMDI)
Simon Lessard1, Stan Langford2
1Université de Montréal, 2Eristan Medical Systems
RATIONALE: The U.S. FDA has long contended that patients are not able to keep track of their aerosol medications, leaving them vulnerable to unwittingly running out of medication. However, the majority of studies supporting this viewpoint rely on surveys and anecdotal evidence. In contrast, this study looks at the physical evidence: that is the contents of inhalers returned to pharmacies by consumers for disposal.
METHODS: Each month a random sampling of post consumer inhalers (N=250 + 250) are collected from a government regulated facility for evaluation. Samples are from retail pharmacies, not institutions. The samples are sorted, weighed, cataloged and the number of remaining doses is determined. In Canada only Advair has an on board counting mechanism. For that reason it is used as control.
RESULTS: Over 50% of the control group samples showed zero doses remaining (plus or minus 20%) compared with only 10% of the inhalers without counters. 15% of the pMDIs were found to be substantially depleted with less than -20 doses, remaining. This suggests that patients may have been without medication for a minimum of 3 days and in many cases for multiple weeks. The remaining 70% of the inhalers had between 21% and 99% of their medication remaining. 5% of inhalers returned for disposal were full, most unprimed.
CONCLUSION: FDA’s assertion that patients are unable to manage their inhaled medications holds true. The results also suggest that knowledge of the number of remaining doses fundamentally changes how patients use their inhalers. If it were public policy that inhalers be equipped with counting mechanisms or that pharmacists be required to weigh inhalers to determine the remaining doses before replenishing them the public would be safer, patient compliance would improve and the amount of waste could be reduced.