Why won’t my doctor prescribe an antibiotic for my respiratory infection? Two Philadelphia doctors explain.

You are suffering with a runny nose, dry cough and low-grade fever. COVID testing is negative and you feel miserable. Nighttime cold relief medicine has helped you get some sleep, but the symptoms are lingering. You begin to think: Is it time to call the doctor for an antibiotic?

For many, this is a relatable scenario as we enter the cold and flu season. The routine may be a little different this season: Many clinicians are increasingly reluctant to prescribe antibiotics.

Antibiotics are drugs that treat bacterial infections and, when needed, are very effective. As it turns out, though, most upper respiratory infections are caused by viruses, for which antibiotics are unhelpful.

In fact, an estimated 50% of antibiotics prescribed for acute upper respiratory conditions are unnecessary and discordant with published guidelines, according to 2020 research published in Clinical Infectious Diseases, a medical journal associated with the Infectious Disease Society of America.

Still, many of our patients ask:

“Why not just try the antibiotic anyway, especially if it seems to have worked in the past?”

Viral respiratory infections generally run their course over a few days to a week. If you do end up on an antibiotic, it is usually started at least a few days into symptoms that will resolve soon anyway, even with no treatment. This may create the impression that the antibiotic has saved the day, when in fact it probably made no difference at all.

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Clinicians used to have a lower threshold for prescribing antibiotics “just in case it may help” an upper respiratory tract infection, but there is now a heightened concern regarding the harm antibiotics may cause, particularly when used inappropriately.

When over-prescribed, antibiotics make people vulnerable to antibiotic-resistant bacteria, which can be dangerous and are difficult to treat.

Antibiotics also have possible side effects and complications, including serious allergic reactions in those who are susceptible to them. One particularly worrisome complication is C. difficile colitis, a potentially dangerous infection of the colon.

While killing the bacteria they are prescribed for, antibiotics also kill normal colonic bacteria, or “flora,” which keep pathogens such as C. difficile at bay. Nonessential use of antibiotics contributes to persistently high rates of C. difficile colitis. A choice not to prescribe antibiotics should never feel as if it is due to mistrust, not taking you seriously, or lack of concern. Rather, it is an effort to provide the best care and avoid harm.

Most important, decisions around treatment for respiratory tract infections should involve a collaborative clinician-patient discussion and clear explanations.

Jeffrey Millstein is a primary-care physician and regional medical director for Penn Primary Care. Lauren Dutcher is an assistant professor of medicine in the division of infectious diseases at the University of Pennsylvania’s Perelman School of Medicine.