About one-quarter of all antibiotics – especially those given out for viral colds, chest infections and coughs – are inappropriately prescribed, according to a new study from the University of Michigan Medical School.
The study looked at the diagnosis codes assigned by health-care workers for more than 19 million privately insured outpatients in the United States in 2016. The findings were published Wednesday in the journal the BMJ.
Viral and bacterial infections sometimes have similar symptoms, but antibiotics are not effective in treating viral infections.
The overuse of antibiotics has become a public health concern, as it has contributed to the rise of “superbugs” that are resistant to even the most powerful drugs. On an individual level, taking antibiotics when they aren’t needed — such as for colds and the flu — can mean they won’t be effective when they are.
Antibiotics promote resistance even when they may be effective against a specific organism, because they kill other microbes in the process, enabling resistant bacteria to multiply.
In the U.S., at least 2 million people get an antibiotic-resistant infection each year, and at least 23,000 people die of these infections, according to the Centers for Disease Control and Prevention.
While there have been efforts to discourage the incorrect use of antibiotics, the U.S. remains the leading user of the drugs worldwide, with 3.3 billion doses administered in 2015.
The study found that three-quarters of the inappropriate prescriptions were written for adults. Women made up half of those patients, according to the study.
About 11 percent of study participants lived in rural areas, with 16 percent from the northeastern states, 17 percent from western states, 20 percent from the Midwest, and 45 percent from the South.
Most of the prescriptions were written in a physician’s office. Nearly 8 percent were prescribed in urgent care centers and about 6 percent in hospital emergency departments.
The most common antibiotics prescribed were azithromycin, amoxicillin, and amoxicillin clavulanate, according to the study.
About one-third of prescriptions were categorized as potentially appropriate, but the researchers stated that even many of these could have been incorrectly administered because they were given for illnesses like sinusitis and sore throats that often are viral.