Urgent care clinics prescribed antibiotics to nearly half of patients who had the flu or a cold but did not have bacterial infections that actually require antibiotics, according to a new study.

The number of antibiotics prescribed by urgent care clinics were three times higher than those of traditional doctors’ offices, the study published by JAMA Internal Medicine found. Side effects and the possible development of “superbugs” that resist treatment with antibiotics are risks of unnecessary prescriptions.

No other study has looked at urgent care centers and retail health clinics, which serve millions of patients in the U.S. from standalone locations or within big box stores and pharmacy chains, The Washington Post reported.

A 2041 report predicted antibiotic-resistant bacteria could kill 10 million people worldwide by 2050, which is more than the number killed by cancer and could cost the global economy $100 trillion.

Overall in the U.S., about one-third of antibiotics, or 47 million prescriptions, are given out each year at doctors’ offices, emergency rooms, and clinics when they aren’t really necessary, a 2016 PEW/CDC study showed, the Post reported. 

Patients often ask for antibiotics and don’t feel they are getting proper treatment when doctors and other medical personnel refuse, the Post reported. Some patients even file complaints or give negative reviews on social media and other sites. 

Deputy Director of the CDC Antibiotic Stewardship Office and study participant Katherine Fleming-Dutra said doctors who communicate clearly why antibiotics are not needed and what patients should do to get better are more likely to have satisfied patients, the Post reported. 

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