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Metronidazole vaginal gel 0.75%

Updated 2 Feb 2023 | Vaginal and vulval infections


Vaginal gel containing metronidazole.

Drugs List

  • metronidazole 0.75% vaginal gel
  • ZIDOVAL 0.75% vaginal gel
  • Therapeutic Indications


    Vaginosis - bacterial



    One application (5g) inserted into the vagina at bedtime for five consecutive days.


    Bacterial vaginosis (unlicensed)
    One application (5g) inserted into the vagina at bedtime for five consecutive days.


    None known

    Precautions and Warnings

    Children under 18 years
    Haematological disorder
    History of haematological disorder

    Contains hydroxybenzoate
    Contains propylene glycol: may cause irritation
    Symptoms of candidiasis may be exacerbated
    May affect results of some laboratory tests
    Not licensed for all indications in all age groups
    Avoid prolonged use
    Advise patient that alcohol ingestion may cause a disulfiram-like reaction
    Advise patients to refrain from sexual intercourse during treatment

    Pregnancy and Lactation


    Use metronidazole with caution in pregnancy.

    Data on a large number (several hundred) of exposed pregnancies indicate no adverse effects of metronidazole on the foetus/newborn child. There have been no formal studies with metronidazole vaginal gel in pregnant women. The manufacturer advises that caution should, therefore, be exercised when prescribing to pregnant women.

    The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14 to 17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( ) or if this is unavailable at the backup site ( ).


    Use metronidazole with caution in breastfeeding.

    Neither topical nor vaginal metronidazole have been studied during breastfeeding. After vaginal administration, plasma levels are less than 2% of those after a 500mg oral dose. After topical administration, blood levels are about 1% of the peak plasma levels after a 250mg oral dose. Manufacturer advises that caution should be exercised when prescribing to breastfeeding women.

    Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
    Specialist advice is available from the UK Drugs in Lactation Advisory Service at

    Side Effects

    "Spotting" bleeding
    Abdominal cramps
    Allergic reaction
    Burning sensation
    Decreased appetite
    Discolouration of urine
    Dry mouth
    Dry skin
    Gastro-intestinal discomfort
    Menstrual discomfort
    Menstrual disturbances
    Metallic taste
    Pelvic discomfort
    Skin discomfort
    Skin irritation
    Skin pain
    Stomach/abdominal gurgling
    Tongue disorder
    Urinary tract infections
    Vaginal candidiasis
    Vaginal discharge
    Vaginal irritation
    Vaginal numbness
    Vulvovaginal burning
    Vulvovaginal itching
    Vulvovaginal swelling

    Effects on Laboratory Tests

    Metronidazole may interfere with certain types of determination of serum chemistry values, such as aspartame aminotransferase (AST, SGOT), alanine aminotransferase (ALT, SGPT), lactic dehydrogenase (LDH), triglycerides and hexokinase glucose. Values of zero may be observed.


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Further Information

    Last Full Review Date: July 2018.

    Reference Sources

    Summary of Product Characteristics: Zidoval. Meda Pharmaceuticals Ltd. Revised March 2018.

    NICE Evidence Services Available at: Last accessed: 02 July 2018

    US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
    Available at:
    Metronidazole. Last revised: 01 May 2018
    Last accessed: 29 June 2018

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