I've taken 3 400mg metronidazole tablets with four hours between each dose. is this ok, i haven't had an accidental over dose? told to take 3 daily

Metronidazole dosing: There is a range of doses for metronidazole. Indeed, it is often given three times a day. I think your doctor adjusted your dose to 400 mg -probably based on your [thin] build. So your total dose for one day is 1,200 mg. A common side effect is nausea, particularly if you take too much. If you have questions about your medication -you should definitely talk to the doctor that prescribed it.