BACKGROUND: While antibiotics are life-saving drugs, their use is not without risk, including adverse events and antibiotic resistance. The majority of US antibiotic prescriptions are prescribed in outpatient settings, making outpatient antibiotic prescribing an important antibiotic stewardship target. The primary objective of this study was to describe trends in US outpatient oral antibiotic prescriptions from 2011-2016. METHODS: We estimated annual oral antibiotic prescription rates using national prescription dispensing count data from IQVIA Xponent, divided by census estimates for 2011-2016. We calculated the ratio of broad- to narrow-spectrum prescriptions by dividing broad-spectrum prescription rates by narrow-spectrum prescription rates. We used Poisson models to estimate prevalence rate ratios, comparing 2011 and 2016 antibiotic prescription rates, and linear models to evaluate temporal trends throughout the study period. RESULTS: Oral antibiotic prescription rates decreased 5%, from 877 prescriptions per 1000 persons in 2011 to 836 per 1000 persons in 2016. During this period, rates of prescriptions dispensed to children decreased 13%, while adult rates increased 2%. The ratio of broad- to narrow-spectrum antibiotics decreased from 1.62 in 2011 to 1.49 in 2016, driven by decreases in macrolides and fluoroquinolones. The proportion of prescriptions written by nurse practitioners and physician assistants increased during the study period; in 2016, these providers prescribed over one-quarter of all antibiotic prescriptions. CONCLUSIONS: Outpatient antibiotic prescription rates, especially of broad-spectrum agents, have decreased in recent years. Clinicians who prescribe to adults, including nurse practitioners and physician assistants, are important targets for antibiotic stewardship.

OBJECTIVE: To describe national antibiotic prescribing for acute gastroenteritis (AGE). SETTING: Ambulatory care. METHODS: We included visits with diagnoses for bacterial and viral gastrointestinal infections from the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey (NAMCS/NHAMCS; 2006-2015) and the IBM Watson 2014 MarketScan Commercial Claims and Encounters Database. For NAMCS/NHAMCS, we calculated annual percentage estimates and 99% confidence intervals (CIs) of visits with antibiotics prescribed; sample sizes were too small to calculate estimates by pathogen. For MarketScan, we used Poisson regression to calculate the percentage of visits with antibiotics prescribed and 95% CIs, including by pathogen. RESULTS: We included 10,210 NAMCS/NHAMCS AGE visits; an estimated 13.3% (99% CI, 11.2%-15.4%) resulted in antibiotic prescriptions, most frequently fluoroquinolones (28.7%; 99% CI, 21.1%-36.3%), nitroimidazoles (20.2%; 99% CI, 14.0%-26.4%), and penicillins (18.9%; 99% CI, 11.6%-26.2%). In NAMCS/NHAMCS, antibiotic prescribing was least frequent in emergency departments (10.8%; 99% CI, 9.5%-12.1%). Among 1,868,465 MarketScan AGE visits, antibiotics were prescribed for 13.8% (95% CI, 13.7%-13.8%), most commonly for Yersinia (46.7%; 95% CI, 21.4%-71.9%), Campylobacter (44.8%; 95% CI, 41.5%-48.1%), Shigella (39.7%; 95% CI, 35.9%-43.6%), typhoid or paratyphoid fever (32.7%; (95% CI, 27.2%-38.3%), and nontyphoidal Salmonella (31.7%; 95% CI, 29.5%-33.9%). Antibiotics were prescribed for 12.3% (95% CI, 11.7%-13.0%) of visits for viral gastroenteritis. CONCLUSIONS: Overall, ∼13% of AGE visits resulted in antibiotic prescriptions. Antibiotics were unnecessarily prescribed for viral gastroenteritis and some bacterial infections for which antibiotics are not recommended. Antibiotic stewardship assessments and interventions for AGE are needed in ambulatory settings.