Customizing Clinical Decision Support to Prevent Excessive Drug–Drug Interaction Alerts

John R. Horn, Pharm.D., FCCP; Philip D. Hansten, Pharm.D; Jacqueline D. Osborn, Pharm.D; Pamela Wareham, B.Pharm; Shabir Somani, M.S., M.B.A


Am J Health Syst Pharm. 2011;68(8):662-664. 

In This Article

Too Many Alerts

Commercial software programs designed to assist pharmacists during prescription processing have included DDI alert software for many years. With the implementation of computerized prescriber order entry (CPOE), DDI software produces prodigious numbers of alerts for both pharmacists and physicians. The commercial DDI software used by the department of pharmacy services at the University of Washington (UW) Medicine Health System produces nearly 25,000 alerts in a typical 24-hour period from approximately 900 inpatient beds. Exposing practitioners to this number of alerts causes user desensitization and alert fatigue.[4,5] Alert fatigue is a major problem with DDI CDS systems and is often the result of DDI software that has poor specificity, with alerts that are considered irrelevant overridden about 90% of the time.[6–10] Computerized DDI CDS does not achieve its intended function when its recommendations are almost universally ignored and "work arounds" are actively pursued.

Alert fatigue leads to inappropriate solutions, such as ignoring almost all alerts or attempting to limit alerts by allowing only the most "severe" alerts to be seen.[11] While turning off whole subsections of alerts is easy to do and will reduce the number of alerts, it is uncommon for anyone who uses this approach to actually review all interactions from this subsection that will no longer alert prescribers. Further, this approach will very likely affect patient safety.[12] Finally, consider how it will appear to outside reviewers (e.g., a jury) when an annoying DDI that was turned off, with no risk assessment, causes harm to a patient.

We have personally heard suggestions to turn off DDI alerts for certain specialists—not drug interaction specialists but rather practitioners who have medical or surgical subspecialty training. Although this sounds like a good idea, in a study of prescribers' knowledge of potential DDIs, specialists scored lower in identifying clinically important DDI pairs than did generalists.[13] Certainly convincing evidence is needed before assuming that some subset of prescribers is less likely to place patients at risk for DDIs.


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