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Metronidazole

Metronidazole is a nitroimidazole antimicrobial that acts on anaerobic bacteria, protozoa and microaerophilic organisms. It is a standard choice for several of these infections, including bacterial vaginosis, trichomoniasis and giardiasis. Tablets are supplied in 200 mg and 400 mg strengths.

Medicine containing Metronidazole

Metronidazole

Bacterial Vaginosis, Trichomoniasis, Giardiasis

200 · 400mg

Metronidazole tablets contain metronidazole, with the price shown per tablet, in several strengths and pack sizes. They are used for bacterial vaginosis, trichomoniasis, giardiasis and protozoal infection.

FromUS$0.31/ tabletView

Key points

  • Onset is within 1 to 2 hours of a dose, and the effect lasts roughly 8 to 12 hours.
  • The medicine may impair motor coordination, so see how it affects you before driving or using machinery.
  • Alcohol, warfarin and lithium are the interactions to check with your doctor before treatment starts.

What metronidazole treats

Metronidazole is used for anaerobic bacterial infections and for protozoal infections. Among the conditions it treats are bacterial vaginosis, trichomoniasis and giardiasis, and it also covers other protozoal infections. It is chosen for some bacterial infections where penicillin-type antibiotics do not work well.

How metronidazole works

The drug is reduced inside susceptible microorganisms, which produces toxic intermediates. These damage DNA and inhibit bacterial nucleic acid synthesis, so the organism cannot grow and multiply.

Metronidazole tablets

Metronidazole is supplied as a tablet in 200 mg and 400 mg strengths. It sits within the antibiotics group, and generic metronidazole contains the same active ingredient whatever the pack is called. Pharmacy partners in India ship orders to Malaysia in discreet packaging.

Safety, side effects and interactions

Do not take metronidazole if you have had a hypersensitivity reaction to a nitroimidazole. It is also contraindicated if you have taken disulfiram within the past two weeks, and it should be avoided in the first trimester of pregnancy. Alcohol must be avoided during treatment. Warfarin and lithium are the other medicines that interact with it, so tell your doctor about everything you take.

Nausea, a metallic taste and headache are the minor effects. Diarrhoea, abdominal discomfort and a furry tongue are also reported. Peripheral neuropathy and seizures are serious and need immediate medical attention. In laboratory animals metronidazole has caused cancer, and anyone with concerns should discuss the risks and benefits with their doctor. Breastfeeding women should use it with caution and stop breastfeeding at high doses. Children can take it when the dose is set by weight.

What the sources say

  • Metronidazole remains a standard choice for anaerobic bacterial, protozoal and microaerophilic infections (NCBI).
  • A boxed warning notes that it may be carcinogenic in animal studies, while follow-up studies of treated patients have not shown an increased cancer incidence (NCBI).
  • Pregnant women generally should not take metronidazole during the first trimester (MedlinePlus).
  • It is contraindicated where disulfiram has been used in the past two weeks (NCBI).

Further reading

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