Antibiotics are designed to specifically treat an infection in a particular part of the body and Metronidazole is used to treat tooth infections, and I have to say that dentists are very fond of prescribing them.
A few years ago I had a tooth infection, after a week of taking Metronidazole, I suffered severe diarrhoea so bad I had to return from holiday.
I went through all the tests, the poking about, the two weeks waiting for an urgent hospital appointment and nothing sinister was found, the antibiotics had totally messed with my stomach.
When the dentist suggested antibiotics after another infection I refused, the infection cleared up on its own with the help of a mouth wash. I will never take Metronidazole again, but I have taken other antibiotics for other infections I have suffered.
Sorry if it all sounds dramatic but that's what happened to me, it might be completely different for you, KaraShannon. X