Antibiotic prescribing in the outpatient setting has decreased considerably in the United States in recent years, according to a large study of Veterans Affairs (VA) facilities.

“We have seen positive steps taken to reduce antibiotic use in VA outpatient clinics, community-based outpatient clinics, emergency departments, and other outpatient settings, and healthcare teams should be congratulated for their ongoing work to reduce unnecessary antibiotic use,” lead researcher Dr. Haley Appaneal said in a news release from the virtual European Congress of Clinical Microbiology and Infectious Diseases where she presented the findings.

The VA is the largest integrated health system in the United States, serving roughly 9.2 million veterans in more than 1,200 outpatient clinics and 140 hospitals.

Dr. Appaneal of Providence VA Medical Center, in Rhode Island, and colleagues assessed dispensed antibiotic prescriptions in the VA outpatient setting between 2011 and 2018 using VA pharmacy datasets.

They calculated the annual number of days of therapy (DOT) per 100 outpatient visits for all antibiotics and then individually for the five most common antibiotics (doxycycline, azithromycin, amoxicillin/clavulanate, ciprofloxacin, and sulfamethoxazole/trimethoprim).

Over the eight-year study period, total antibiotic prescriptions dispensed in the community fell significantly by an average of 3.9 percent per year, from 39.6 DOT per 100 visits in 2011 to 29.4 DOT per 100 visits in 2018.

The biggest decline was in the use of ciprofloxacin, a broad-spectrum antibiotic, which dropped by an estimated 12.6 percent on average per year.

The use of sulfamethoxazole/trimethoprim, used commonly for urinary-tract infections, also decreased substantially (by around 7 percent a year).

However, between 2011 and 2018, outpatient prescriptions remained unchanged and were high for three antibiotics: doxycycline (often used to treat skin infections and sexually transmitted infections), azithromycin (widely used for chest, nose, and throat infections), and amoxicillin/clavulanate (used for respiratory and other infections).

“Use of these three commonly prescribed antibiotics remain high and may be an appropriate target for antibiotic stewardship programs in the VA to further reduce inappropriate outpatient prescribing,” Dr. Appaneal said.

“It might also help combat resistance if national guidelines took stewardship principles into account when making disease-specific recommendations for antibiotic use,” she added.

While antibiotics are “essential” for treating serious bacterial infections, such as sepsis, pneumonia and meningitis, “they should not be used to treat acute respiratory conditions such as asthma, coughs, earache and sore throats, which do not respond to these drugs. Antibiotic resistance is not just a matter for clinicians – the public also have a crucial role to play in helping to preserve these vital medicines,” Dr. Appaneal concluded.