Background:The medication prescribing, and de-prescribing process is complex with numerous actors, organizations, and health information technology (IT). CancelRx is a health IT that automatically communicates medication discontinuations from the clinic electronic health record to the community pharmacy’s dispensing platform, theoretically improving communication. CancelRx was implemented across a Midwest academic health system in October 2017.Objective:The goal of this study was to describe how both the clinic and community pharmacy work systems change and interact over time regarding medication discontinuations.Approach:Medical Assistants (n = 9), Community Pharmacists (n = 12), and Pharmacy Administrators (n =3), employed by the health system were interviewed across 3-time periods— 3-months prior to CancelRx implementation, 3-months after CancelRx implementation, and 9-months after CancelRx implementation. Interviews were audio recorded, transcribed, and analyzed via deductive content analysis.Key Results:CancelRx changed the medication discontinuation process at both clinics and community pharmacies. In the clinics, the workflows and medication discontinuation tasks changed over time while MA roles and clinic staff communication practices remained variable. In the pharmacy, CancelRx automated and streamlined how medication discontinuation messages were received and processed, but also increased workload for the pharmacists and introduced new errors.Conclusions:This study utilizes a systems approach to assess disparate systems within a patient network. Future studies may consider health IT implications for systems that are not in the same health system as well as assessing the role of implementation decisions on health IT use and dissemination.