WATERLOO (KWWL) - Antibiotics are designed to kill off harmful bacteria, but a new study suggests repeated use may get rid of "good" bacteria, too.
The Stanford study looked at the effect of two rounds of the antibiotic Cipro on bacteria in the stomach.
Over the course of a year, researchers noted subtle effects of the antibiotic usage, mainly that it altered the composition of beneficial bacteria in the gut.
Researchers say this does not mean Cipro is dangerous or should be avoided -- just that further study of long-term effects of antibiotics is needed.
Online reporter/anchor: Tara Thomas