How do metronidazole tablets work?
Metronidazole is an antibiotic which works most effectively against anaerobic bacteria. Anaerobic bacteria do not require oxygen to live. When a woman has bacterial vaginosis (BV), anaerobic bacteria replace the lactobacilli which usually maintain a healthy vaginal environment. Metronidazole kills the anaerobic bacteria allowing the lactobacilli to take over again and restore the natural balance in the vagina.
Dosage regime for metronidazole 400mg tablets
There are many different regimes for taking metronidazole tablets, depending on the infection being treated. For BV, there are also a few possible regimes. Dr Fox supplies 14 x 400mg tablets to be taken twice daily 12 hours apart for 7 days – swallow whole with water, with a meal.
Note: metronidazole 400mg is supplied from the manufacturers in boxes of 21 tablets. You will receive an opened or blank box with 14 tablets only.
Alternative treatments for bacterial vaginosis
There are several alternative prescription treatments for BV. Always use medication according to the regime actually prescribed for you.
Metronidazole tablets
- 400mg tablets twice a day for 5-7 days.
- 500mg tablets twice a day for 5-7 days.
- One dose of 2 grams (5 x 400mg tablets or 4 x 500mg tablets) all at once.
Clindamycin tablets
- 300mg tablets twice a day for 7 days.
- Usually reserved for pregnancy.
Metronidazole 0.75% vaginal gel (Zidoval)
Every night for 5 nights.
Clindamycin 2% vaginal cream (Dalacin)
Every night for 7 nights.
Most treatments have been shown to be equally effective with 70-80% cure rates. However the large one-off dose of 2 grams of oral metronidazole was slightly less effective in trials and is more likely to cause side effects.
Cautions when taking metronidazole 400mg tablets
- Metronidazole should not be used in severe liver failure.
- Metronidazole may aggravate neurological diseases.
- Kidney disease or dialysis may require altered dosing – specialist advice required.
- Manufacturers advise not to drink alcohol whilst taking metronidazole 400mg tablets and for the 48 hours afterwards. Taking alcohol with metronidazole may cause a ‘disulfiram reaction’. Disulfiram is given to people with alcoholism, to help them to stop drinking alcohol. It causes a bad reaction when alcohol is taken. The disulfiram reaction includes nausea, vomiting, dizziness, chest, head and abdominal pains. See also






Reviews
There are no reviews yet.