In an EHR with CPOE and CDS, when should allergy alerts be triggered?

• A. After orders are written
• B. In response to contraindicated drug orders
• C. Before orders are written
• D. On physician request by accessing a link

Answer: (C)

Allergy alerts are safest and most effective when they appear in real time during the ordering process, before an order is finalized. This allows the clinician to see a potential allergy clash as they are selecting a drug, and to choose an alternative or document a valid rationale before anything is prescribed. If the alert only fires after the order is written, there’s a real risk that the patient could be exposed to the allergic drug before anyone notices. While CDS can flag contraindicated orders, waiting for that determination to occur after the order is placed is not timely enough to prevent harm. Relying on a physician to click a link on demand would also fail to provide immediate, proactive safety checks within the workflow.