For certain infections you may be given a single, larger dose of metronidazole, usually five 400 mg tablets (2 g) to take at once. Take each of your doses with a snack or just after eating a meal. Swallow the tablets whole (that is, without chewing or crushing them) with a full glass of water. Metronidazole is an antibiotic that fights bacteria. Metronidazole is used to treat bacterial infections of the vagina, stomach or intestines, liver, skin, joints, brain, heart, and respiratory tract. 7.5 mg/kg every 8 hours (max. per dose 400 mg) usually treated for 7 days (for 10–14 days in Clostridium difficile infection). For Child 12–17 years 400 mg every 8 hours usually treated for 7 days (for 10–14 days in Clostridium difficile infection). Metronidazole is an antibiotic used to treat certain types of bacterial and parasitic infections. It's known to react badly with alcohol and may cause a number of unpleasant side effects. Metronidazole is indicated in the prophylaxis and treatment of infections in which anaerobic bacteria have been identified or are suspected to be the cause. Low-dose oral metronidazole, 200-400 mg three times daily, produces milk levels only slightly lower than corresponding levels in maternal plasma (76 to 99%). Doses up to 500 mg three times daily for a 7 to 10 day course are considered to be compatible with breastfeeding. Metronidazole for bacterial infections. This leaflet is about the use of metronidazole for bacterial infections. This leaflet has been written specifically for parents and carers about the use of this medicine in children. Metronidazole tablets must not be taken during the first 3 months of pregnancy and should not be taken during the rest of the pregnancy. If you breastfeed you should stop whilst taking Metronidazole tablets and for 12-24 hours after the course of tablets has finished before breastfeeding again. Metronidazole is an antibiotic. It's used to treat skin infections, rosacea and mouth infections (including infected gums and dental abscesses). It's used in the treatment of conditions such as bacterial vaginosis and pelvic inflammatory disease. Pricing, sizing, legal catgories and other medicinal forms information for METRONIDAZOLE.