BACKGROUND: We decided to inform our patients of the withdrawal of rofecoxib, one of the largest drug withdrawals in United States history, and instruct them to contact their providers for guidance. OBJECTIVE: To identify and inform patients and providers affected by the rofecoxib withdrawal. DESIGN: Descriptive observational study. SETTING: Tertiary care center with an electronic medical record (EMR) system. PATIENTS: Patients with an active rofecoxib prescription within the EMR. INTERVENTION: Existing information technology and traditional communication resources were used to automate the identifying and notifying of patients and providers and to deactivate rofecoxib prescriptions in the EMR. MEASUREMENTS: Characteristics of patients receiving rofecoxib at our institution, details of their prescription and provider, number of EMR alerts, and medication discontinuations. RESULTS: The 11,699 patients with a rofecoxib prescription in our practice were sent notifications within 24 hours of the withdrawal. LIMITATIONS: We did not directly measure the effect of our notification on patients or providers. CONCLUSIONS: Information technology enabled our institution to rapidly identify and notify individual patients and their providers about an important drug withdrawal. The methods modeled a feasible way for health care organizations with EMRs to participate in notification processes that may be applicable in a variety of situations.