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  • Metronidazole 400mg Tablets (21s)

  • Metronidazole 400mg Tablets
  • Flagyl , an antibiotic, contains the active ingredient metronidazole. Metronidazole is used to treat infections caused by bacteria and other micro-organisms called protozoa.

    Metronidazole inhibits the synthesis of bacterial and protazoal genetic material (DNA). This prevents the bacteria and protozoa from forming new DNA ultimately resulting in their death. White blood cells “eat” the dead micro-organism and the infection clears up.

    Metronidazole kills a wide variety of bacteria that are known collectively as anaerobic bacteria. This means that they do not need oxygen to grow and multiply. Anaerobic bacteria can cause infections in areas of the body such as the bones, gut, pelvic cavity and gums. Metronidazole is used to treat these types of infections, as well as leg ulcers and pressure sores that are infected with anaerobic bacteria.

    Metronidazole is also used to treat infections with protozoa. These micro-organisms are also anaerobic and include Trichomonas vaginalis, which is the cause of  the sexually transmitted infection trichomoniasis.

    The dose of metronidazole prescribed, how often to take it and for how long, all depend on the type and severity of infection being treated (or prevented), as well as your age and liver function.

    It is important to follow the instructions given by your doctor. These will be printed on the dispensing label that your pharmacist has put on the packet of medicine.

    Metronidazole tablets should be taken with plenty of water with or after food. The tablets should be swallowed whole and not chewed. Try to space your doses evenly throughout the day.

    Unless your doctor tells you otherwise, it is important that you finish the prescribed course of metronidazole, even if you feel better or it seems the infection has cleared up. Stopping the course early increases the chance that the infection will come back and that the bacteria will grow resistant to the antibiotic.

    Do not drink alcohol while taking metronidazole and for at least 48 hours after finishing the course, as this can cause unpleasant symptoms such as hot flushes, abdominal cramps, nausea, vomiting, headache and palpitations.

    Medicines and their possible side effects can affect individual people in different ways. Just because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect. The following are some of the side effects that are known to be associated with metronidazole. The majority of these side effects are very rare:

    • Disturbances of the gut such as diarrhoea, nausea, vomiting or abdominal pain.
    • Unpleasant taste.
    • Sensation of a furry tongue.
    • Inflamed and sore mouth.
    • Loss of appetite.
    • Severe swelling of lips, face or tongue (angioedema).
    • Drowsiness.
    • Dizziness.
    • Headache.
    • Shaky movements and unsteady walk (ataxia).
    • Skin rashes or itching.
    • Pain in the muscles or joints.
    • Darkening of the urine.
    • Visual disturbances.
    • Confusion.
    • Depressed mood.
    • Hallucinations.
    • Liver disorders.
    • Disorder of the peripheral nerves called peripheral neuropathy that causes weakness and numbness (on prolonged or intensive therapy).
    • Decrease in the number of white blood cells in the blood (leucopenia).
    • Seizures.

    The side effects listed above may not include all of the side effects reported by the medicine's manufacturer. For more information about any other possible risks associated with metronidazole, please read the information provided with the medicine or consult your doctor or pharmacist.

    Do not drink alcohol while taking metronidazole and for at least 48 hours after finishing the course, as this can cause unpleasant symptoms such as hot flushes, abdominal cramps, nausea, vomiting, headache and palpitations.

    Metronidazole should be used with caution in:

    • Decreased liver function.
    • Brain disease that has occurred as a result of liver disease (hepatic encephalopathy).
    • People with diseases of the brain or spinal cord.
    • Hereditary blood disorders called porphyrias.

    Metronidazole should NOT be used in:

    • People with known sensitivity or allergy to any of the ingredients.

    If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.

    The patient information leaflet (PIL) is a leaflet containing specific information about medical conditions, doses and side effects. You can download a copy of the PIL here:

    Patient Info Leaflet Metronidazole 400mg Tablets Information Leaflet