More than a quarter of people who went to emergency departments (EDs) in the United States between 2016 and 2021 received inappropriate antibiotic prescriptions. Nearly half of those who received antibiotics didn’t have a reasonable indication for antibiotics, according to a report published Tuesday in Antimicrobial Stewardship & Healthcare Epidemiology.

Researchers used data from the National Hospital Ambulatory Medical Care Survey, which includes patient characteristics, up to five diagnosis codes and details on up to 30 medications prescribed. The team assessed emergency room visits among people who received one or more oral antibiotic prescriptions between 2016 and 2021. Investigators broke down diagnostic codes into “always,” “sometimes” or “never” to justify if getting an antibiotic was appropriate, potentially appropriate or inappropriate.

Of the more than 152 million ED visits with one or more antibiotic prescriptions given, 27.6% were inappropriately prescribed, while 14.9% were inappropriate with a plausible indication (such as bronchitis). A total of 12.6% had diagnostic codes that weren’t considered plausibly antibiotic-related, which included ailments such as high blood pressure, chest pain and joint pain. Overall, 54% of the visits with inappropriate prescribing had a plausible indication.

Inappropriate antibiotic prescribing in EDs was the most prevalent in adults 18 to 64, as 29.8% of people in that group received the drugs inappropriately compared with 24.6% of adults 65 and older and 23.7% of children. Inappropriate prescribing with reasonable indications was highest in 16.7% of children followed by 15% of working-age adults and 12.6% older adults.

The authors pointed out that the visits with inappropriate prescribing and no plausible coded indication for antibiotics could have been in scenarios in which the antibiotics were needed, but the clinician didn’t code the issue correctly (or avoided proper coding for other reasons). 

“Findings suggest that emergency department antibiotic stewardship initiatives should focus both on reducing antibiotic prescribing for infectious, antibiotic-inappropriate conditions and on improving coding quality for antibiotic prescriptions,” the authors wrote.