One way to limit liability risk is to minimize the likelihood of adverse drug reactions. Electronic prescribing systems are supposed to accomplish that goal by warning of patient allergies or possible interactions with other medications.

A recent study, however, finds the systems are so hypersensitive that “most alerts may be more of a nuisance than an asset,” according to a report in Archives of Internal Medicine (2009;169:305-311). After analyzing 233,537 alerts generated from 3.5 million prescriptions, a team of Harvard internists found clinicians overrode the warnings much more often than not and relied on their own judgment instead.

About one in 15 prescriptions (6.6%) generated an alert. Almost all the alerts (98.6%) were for potential interactions with medications the patient was already taking, but clinicians accepted only 9.2% of these warnings, either changing or canceling their treatment plans. The other alerts were for potential allergies. Those were rejected in 77% of instances.

“Too many alerts are generated for unlikely events, which could lead to alert fatigue,” observed lead author Thomas Isaac, MD, MBA, MPH, an internist at Beth Israel Deaconess Medical Center in Boston.

Prescribers accepted 2.2%-43.1% of alerts to potentially high-severity interactions, depending on the classes of medications involved. Clinicians were less likely to accept these alerts if the patient had already used the medication.

For example, prescribers overrode 97.8% of high-severity alerts concerning topical corticosteroids with anti-infectives and antihyperlipidemic combinations (e.g., topical betamethasone-clotrimazole and ezetimibe-simvastatin). The best high-severity acceptance rate (43.1%) was recorded for noncardioselective beta blockers and macrolides e.g., sotalol and azithromycin.

“We need to find a way to help clinicians separate the proverbial wheat from the chaff,” explained Saul N. Weingart, MD, PhD, vice president for patient safety at Dana-Farber Cancer Institute, also in Boston, and an internist at Beth Israel Deaconess. “Until then, electronic prescribing systems are poised to fall short of their promise to enhance patient safety and to generate greater efficiencies and cost savings.”

Based on these findings, the study recommends that systems

  • Reclassify severity ratings, especially for alerts that are often overridden;
  • Allow users to suppress alerts for medications a patient has already received; and
  • Customize alerts for the prescriber’s specialty.

The researchers also compiled a list of potentially dangerous interactions based on those alerts that most often changed the clinicians’ decision to prescribe. It is available at www.dana-farber.org/pat/patient-safety/docs/e-Rx-alerts.pdf, accessed April 13, 2009.

“Electronic prescribing clearly will improve medication safety, but the full benefit will not be realized without the development and integration of high-quality decision support systems to help clinicians better manage medication safety alerts,” Dr. Weingart commented.