Using the National Poison Data System to Detect Mistaken Oral Ingestions of Medication Capsules Designed for Use in Pulmonary Inhalers

Abstract

Introduction In 2006, the Institute of Medicine proposed initiatives to decrease medication errors using hospital monitoring systems for adverse event (AE) surveillance. Serendipitously, several poison center clinicians noticed a trend of inadvertent oral ingestions involving formoterol fumarate and tiotropium bromide. Each product is packaged in capsules for insertion into special pulmonary inhaler devices for chronic pulmonary disease. The National Poison Data System (NPDS) is a near real-time data and surveillance system capable of tracking AEs. Our objective was to assess the feasibility of NPDS to analyze outpatient AEs, employing formoterol and tiotropium ingestions as a model. Methods Retrospective review of NPDS data for formoterol and tiotropium mistaken oral ingestions (MOI) (2001–2007). Inclusion criteria were age over 6 years, exposures, all administration routes, all reasons, incorrect dosing route, and all medical outcomes. Primary outcome measures were number of MOI cases and demographics of at-risk patients. Results There were 3,919 formoterol and 18,096 tiotropium cases that met inclusion criteria. MOI cases with minor or moderate outcomes were formoterol 82 (2.2%) and tiotropium 131 (0.8%). Neither drug had a major medical outcome or death. Mean age and gender were similar for both medications. MOI was more common among female patients. Health care facility MOIs accounted for 19 (0.5%) formoterol and 35 (0.2%) tiotropium cases. From 2005 to 2007, formoterol and tiotropium cases accounted for 35% to 45% of all NPDS-tracked AEs. Conclusion NPDS data analysis revealed the magnitude of AEs for capsule-shaped medications for inhaler use was more common than previously identified.