Antibiotics, it’s widely known, can wipe out a person’s “good” microbes along with the bad — sometimes leading to nasty side effects like diarrhea or serious infections. But new research finds that antibiotics aren’t alone in their bacterial slaughter: Nearly 1 in 4 other prescription medications, from antipsychotics to antivirals, kill off gut microbes. That could mean old drugs could have new uses — or have hidden impacts on antibiotic resistance.
Athanasios Typas, a researcher at the European Molecular Biology Laboratory, and his team tested more than 1,000 FDA-approved drugs from the Prestwick Chemical Library, often used as a screening library, against nearly 40 common microbial species, including Roseburia intestinalis, C. difficile, and two types of Bacteroides fragilis. They found that about 25 percent of drugs tested could reduce the growth of microbes frequently found in a human gut, including almost all antipsychotic medications they tested. “For us, that was much more than we expected,” Typas said. The results were published in Nature on Monday.