It was prescribed for a stomach infection from a prior antibiotic that took all my good and bad bacteria out of my system. I had a tooth infection and the dentist failed to tell me that I needed to take acidopholus with this antibiotic. So now I've taken the metronidazole for the bacteria infection but still have diarhea after I eat after finishing the prescription. Is there something else going on or is it a side effect from the meds?