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Other brands with the same active ingredient
These brands contain the same active ingredient (Metronidazole). Same strength and form. Confirm the switch with your doctor or pharmacist.
Indications & Uses
Metonidazole is indicated for:
Pharmacology
Metronidazole belongs to the imidazole group of antibacterial medicines and is used therapeutically as an antiprotozoal agent. Once inside anaerobic organisms, its 5-nitro group undergoes metabolic reduction. Research has shown that this reduced form then interacts with the organism's DNA, which is how Metronidazole achieves its bactericidal effect.
Dosage Reference
Reference Information Only
Dosages shown are general references from official sources. Always consult your doctor or pharmacist for personalized dosing.
Adults:
For tablets and suspension, the dosing depends on the condition being treated. For trichomoniasis in adults and children over 10 years, the usual dose is 200 mg three times a day, or 400 mg twice a day, for 7 days; alternatively, 800 mg in the morning with 1 to 2 g at night for 2 days, or 2 g as a single dose for 1 day. For trichomoniasis in children, those aged 7 to 10 years take 100 mg three times a day, those aged 3 to 7 years take 100 mg twice a day, and those aged 1 to 3 years take 50 mg three times a day. For intestinal amoebiasis in adults and children over 10 years, the dose is 800 mg three times a day for 5 days. For intestinal amoebiasis in children, those aged 7 to 10 years take 400 mg three times a day, those aged 3 to 7 years take 200 mg four times a day, and those aged 1 to 3 years take 200 mg three times a day. For extra intestinal and asymptomatic amoebiasis in adults and children over 10 years, the dose is 400 to 800 mg three times a day for 5 to 10 days. For extra intestinal and asymptomatic amoebiasis in children, those aged 7 to 10 years take 200 to 400 mg three times a day, those aged 3 to 7 years take 100 to 200 mg four times a day, and those aged 1 to 3 years take 100 to 200 mg three times a day. For giardiasis in adults and children over 10 years, the dose is 2 g once daily for 3 days. For giardiasis in children, those aged 7 to 10 years take 1 g once daily, those aged 3 to 7 years take 600 to 800 mg once daily, and those aged 1 to 3 years take 500 mg once daily. For acute ulcerative gingivitis in adults and children over 10 years, the dose is 200 mg three times a day for 3 days. For acute ulcerative gingivitis in children, those aged 7 to 10 years take 100 mg three times a day, those aged 3 to 7 years take 100 mg twice a day, and those aged 1 to 3 years take 50 mg three times a day. For acute dental infections in adults and children over 10 years, the dose is 200 mg three times a day for 3 to 7 days. For bacterial vaginosis in adults and children over 10 years, the dose is 400 mg twice a day for 7 days, or 2 g as a single dose for 1 day. For leg ulcers and pressure sores in adults and children over 10 years, the dose is 400 mg three times a day for 7 days. For anaerobic infections in adults and children over 10 years, the dose is 800 mg initially, then 400 mg three times a day for 7 days. For anaerobic infections in children aged 1 to 10 years, the dose is 7.5 mg per kg three times a day. For surgical prophylaxis in adults and children over 10 years, the dose is 400 mg three times a day, started 24 hours before surgery, for 1 day. For surgical prophylaxis in children aged 1 to 10 years, the dose is 7.5 mg per kg three times a day.
For the vaginal gel, the recommended dose is one applicator full of Metronidazole gel, approximately 5 grams containing approximately 37.5 mg of Metronidazole, given intravaginally once or twice a day for 5 days. When used once a day, the gel should be applied at bedtime.
For suppositories used in anaerobic infections, adults take 1 g every 8 hours for 3 days, then 1 g every 12 hours. Children aged 5 to 10 years take 500 mg every 8 hours for 3 days, then every 12 hours; children over 10 years follow the adult dose. For surgical prophylaxis with suppositories, adults take 1 g 2 hours before surgery, with up to 3 further doses of 1 g given every 8 hours for high risk procedures. Children aged 5 to 10 years take 500 mg 2 hours before surgery, with up to 3 further doses of 500 mg given every 8 hours for high risk procedures.
For IV infusion, Metronidazole intravenous infusion requires no dilution and should not be mixed with any other drugs before administration. Adults and children over 12 years are infused with 500 mg every 8 hours at a rate of 5 ml per minute, and a maximum of 4 g should not be exceeded during a 24 hour period. Treatment for 7 days is sufficient for most patients, but treatment can be extended, especially where reinfection is likely. For surgical prophylaxis, a dose given shortly before surgery should be followed by doses every 8 hours for the next 24 hours. Children under 12 years are given 7.5 mg per kg of body weight per day, in doses every 8 hours, at a rate of 5 ml per minute.
Side Effects
Metronidazole treatment may cause a metallic taste in the mouth, along with nausea, vomiting, diarrhoea, drowsiness, or skin rashes in some people.
Cautions & Contraindications
Warnings & Precautions
If, for compelling reasons, Silmet needs to be given for longer than the usually recommended duration, regular hematological testing (especially leucocyte count) is advised, and patients should be monitored for adverse reactions such as peripheral or central neuropathy (for example, paresthesia, ataxia, dizziness, or convulsive seizures). Silmet should be used cautiously in patients with hepatic encephalopathy. Patients should be warned that Silmet may darken the urine.
Contraindications
Metronidazole should not be used by patients who are known to be hypersensitive to metronidazole or to any other nitroimidazole-derivative medicine.
Pregnancy & Breastfeeding
Metronidazole carries a US FDA pregnancy category of B. That said, there are no adequate and well-controlled studies in pregnant women. Animal reproduction studies don't always predict how humans will respond, so metronidazole should be used during pregnancy only when it is clearly needed. Metronidazole has been shown to pass into human milk, so care is needed when it is given to a woman who is breastfeeding.
⚠️ Talk to your doctor before taking any medicine during pregnancy or while breastfeeding.
Use in Special Populations
Hepatic impairment: Metronidazole is broken down mainly by oxidation in the liver. When liver failure is advanced, the body may clear Metronidazole much more slowly. In patients with hepatic encephalopathy, the medicine can build up to a large extent, and the high plasma levels that result may add to the symptoms of the encephalopathy. So Metronidazole should be given with caution to these patients. The daily dose should be cut to one third, and it may be given once daily. Patients should be told that Metronidazole may darken their urine.
Renal impairment: In renal failure the elimination half-life of Metronidazole stays the same, so the dose does not need to be reduced. These patients do retain the metabolites of Metronidazole, though, and what this means clinically is not known at present. In patients on haemodialysis, Metronidazole and its metabolites are removed efficiently during an eight hour session of dialysis. Because of this, Metronidazole should be given again straight after haemodialysis. Patients with renal failure who are on intermittent peritoneal dialysis (IDP) or continuous ambulatory peritoneal dialysis (CAPD) need no routine change in dose.
Overdose
Single oral doses of Metronidazole of up to 12 g have been reported in suicide attempts and accidental overdoses. The symptoms were limited to vomiting, ataxia and slight disorientation. There is no specific antidote for Metronidazole overdose. If a massive overdose is suspected, symptomatic and supportive treatment should be started.
⚠️ In an emergency call 999 or go to the nearest hospital emergency department.
Storage
Store Metronidazole below 30°C and keep it protected from light. Keep it out of the reach of children, as you would any medicine. Don't use it after the date of expiry.
Drug Interactions
Common questions about Metonidazole 400 mg
What is Metonidazole 400 mg Tablet?
Metonidazole 400 mg Tablet is a medicine that contains Metronidazole. It is made by Icon Pharmaceuticals. It belongs to the Amoebicides group of medicines.
What is Metonidazole used for?
Metonidazole is used for: Amoebiasis, Giardiasis, Sepsis.
What are the side effects of Metonidazole?
Metronidazole treatment may cause a metallic taste in the mouth, along with nausea, vomiting, diarrhoea, drowsiness, or skin rashes in some people.
Can I take Metonidazole during pregnancy or while breastfeeding?
Metronidazole carries a US FDA pregnancy category of B. That said, there are no adequate and well-controlled studies in pregnant women. Talk to your doctor before taking any medicine during pregnancy or while breastfeeding.
What happens if I take too much Metonidazole?
Single oral doses of Metronidazole of up to 12 g have been reported in suicide attempts and accidental overdoses. The symptoms were limited to vomiting, ataxia and slight disorientation. In an emergency call 999 or go to the nearest hospital emergency department.
How should I store Metonidazole?
Store Metronidazole below 30°C and keep it protected from light. Keep it out of the reach of children, as you would any medicine.
Can I take other medicines with Metonidazole?
Some medicines can interact with Metronidazole, for example: Fluorouracil, Phenytoin, Phenobarbital, Chloroquine Phosphate, Lithium Carbonate, Lactic acid + Citric acid + Potassium bitartrate. Tell your doctor or pharmacist about every medicine you take.
Do I need a prescription for Metonidazole?
Metonidazole is a prescription (Rx) medicine. Take it as your doctor advises.