AIMS, Winter 2019

Incidents Associated with Missed Medication Doses: A Multi-Incident Analysis

ISMP Winter2019
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Larry Sheng, BSc, PharmD Student 1
Carolyn Kasprzak, RPh, PharmD, BCGP 2
Edmond Chiu, RPh, BSc, PharmD 2
Adrian Boucher, RPh, BSc, PharmD 2
Certina Ho, RPh, BScPhm, MISt, MEd, PhD 2,3
1 School of Pharmacy, University of Waterloo
2 Institute for Safe Medication Practices Canada
3 Leslie Dan Faculty of Pharmacy, University of Toronto


An aging population and increasing medication use imply that pharmacies and patients may be at risk of experiencing errors that involve missed medication doses. Missed medication doses can attenuate or eliminate a drug’s therapeutic effects resulting in suboptimal disease management, more frequent physician visits, and higher hospitalization rates.1 For some medications, such as warfarin, even a few missed doses can reduce its beneficial effects and result in serious adverse events, such as a stroke.2 Missed doses can also cause withdrawal symptoms with some medications, such as antidepressants, resulting in side effects such as flu-like symptoms, anxiety, and electric shock-like sensations.3,4

Factors, such as pharmacy environments, complex medication regimens, and training of pharmacy staff can contribute to incidents associated with missed medication doses. Identifying and addressing the root causes that may lead to these incidents in community pharmacy practice can have a significant positive impact on patient care and medication safety.

This multi-incident analysis aims to identify overarching themes encompassing underlying contributing factors that result in incidents associated with missed medication doses reported by community pharmacies. Additionally, this analysis targets vulnerable medication-use processes in community pharmacy settings in order to develop recommendations to mitigate the risk of future incidents associated with missed doses, and to optimize patient safety outcomes through safe medication practices.


Incidents included in this analysis were voluntarily reported by pharmacy professionals to the Institute for Safe Medication Practices Canada (ISMP Canada) Community Pharmacy Incident Reporting (CPhIR program. We extracted incidents with “Omitted Medication/Dose” reported as the primary type of incident from the CPhIR database between July 1, 2016 and June 30, 2017.

Using the specified inclusion criteria, an initial search yielded a total of 194 incidents. After removing duplicate entries and non-viable incidents (e.g. incidents with insufficient details, ambiguous description, etc.), a total of 156 incidents were included and subjected to a qualitative, multi-incident analysis, which was conducted by four independent medication safety analysts. Themes, sub-themes, contributing factors, and recommendations to address patient safety gaps corresponding to incidents associated with missed medication doses were then derived from this analysis.


We identified three main themes and corresponding sub-themes. Along with contributing factors and potential recommendations, they are listed in Tables 1 to 4 below. We would also like to bring your attention to the following previous Multi-Incident Analyses that have been published in Pharmacy Connection, as most incidents reviewed in this analysis that were associated with missed medication doses were identified during some of the high-risk processes in community pharmacy workflow.


Despite pharmacy professionals’ best efforts to provide safe and effective pharmaceutical care, errors cannot be 100% eliminated. Whether errors are related to a lack of communication among healthcare practitioners, or from an inadequate medication management system, it is essential to recognize the importance of being proactive in addressing the root causes. In this analysis, we described some of the contributing factors that may lead to missed medication doses and offer recommendations to prevent these incidents from occurring. Findings from this multi-incident analysis will help target areas of risk associated with missed medication doses and support making changes to improve medication safety in your pharmacy.


The authors would like to acknowledge Dr. Puja Modi for her assistance in conducting this multi-incident analysis. Dr. Modi completed a PharmD rotation at the Leslie Dan Faculty of Pharmacy, University of Toronto, and ISMP Canada in 2017. ISMP Canada would like to acknowledge support from the Ontario Ministry of Health and Long-Term Care for the development of the Community Pharmacy Incident Reporting (CPhIR) Program (

The CPhIR Program contributes to the Canadian Medication Incident Reporting and Prevention System (CMIRPS) ( A goal of CMIRPS is to analyze medication incident reports and develop recommendations for enhancing medication safety in all healthcare settings. The incidents anonymously reported by community pharmacy practitioners to CPhIR were extremely helpful in the preparation of this article.

Table 1. Summary of Themes table

Table 2. Compliance Packaging Table

Table 3. Transition of Care table

Table 4. Medication Distribution table

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