Despite abundant evidence showing that antibiotics don’t work against viral infections, many doctors still prescribe them -- especially amoxicillin -- for lower respiratory infections such as bronchitis, even after ruling out pneumonia. That’s because a few scant studies have indicated that it might help, at least a little bit, in shortening the severity or duration of symptoms.

That practice should change if medical practictioners follow the latest research published Wednesday in the journal Lancet. The European researchers randomly assigned amoxicillin or placebos to more than 2,000 patients diagnosed with bronchitis because of severe coughs, chest congestion, and other cold symptoms lingering for more than a week. They found that not only did antibiotics fail to alleviate or resolve symptoms faster than a placebo, but the drugs were more likely to lead to side effects including nausea, diarrhea, or rashes.