Inappropriate Antibiotic Prescribing for Acute Bronchiolitis in US Emergency Departments, 2007-2015.

One-fourth of patients with bronchiolitis seen in US emergency departments between 2007 and 2015 received antibiotics; 70% of them had no documented bacterial coinfection. Macrolides were prescribed in 38% of the cases. Antibiotic use did not decrease after national recommendations against routine prescribing. Efforts are needed to reduce unnecessary and inappropriate antibiotic use for bronchiolitis.