A vaginal antibacterial for bacterial vaginosis
Dequalinium
A vaginal antibacterial tablet used to treat bacterial vaginosis by reducing the overgrowth of bacteria that causes the symptoms.
What is Dequalinium?
Dequalinium is a vaginal antibacterial used to treat bacterial vaginosis (BV) — an imbalance of vaginal bacteria that can cause a fishy-smelling discharge. It is inserted into the vagina as a tablet. It is not an antibiotic by mouth, and it should be avoided during a period.
Education and reference only. This is a plain-language guide to Dequalinium — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Dequalinium is a vaginal antibacterial used to treat bacterial vaginosis (BV), a common condition where the normal balance of bacteria in the vagina is disturbed, often causing a thin, greyish, fishy-smelling discharge. It is inserted into the vagina as a tablet over a short course. It offers an alternative to antibiotic tablets or gels for treating BV.
How it works
In bacterial vaginosis the helpful lactobacilli that normally keep the vagina slightly acidic are crowded out by an overgrowth of other bacteria. Dequalinium is an antiseptic-type agent that damages the outer membranes of these bacteria over a wide range, reducing their numbers. As the overgrowth settles, the normal healthier balance and acidity can re-establish and the symptoms ease.
Company & origin
Originated / developed by: Bayer.
Dequalinium is an antiseptic antibacterial agent long used in throat lozenges, and a vaginal tablet form is available in the UK to treat bacterial vaginosis.
Practical use
How to take Dequalinium
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Insert the tablet high into the vagina, usually at bedtime so it stays in place overnight.
- Avoid using it during your period; time the course so it does not overlap with bleeding.
- Complete the full course even if symptoms improve quickly.
- Avoid vaginal washes, douches and spermicides during treatment, as they can interfere with it.
- See a clinician if symptoms do not settle, keep returning, or you are pregnant.
Weighing it up
Advantages & disadvantages of Dequalinium
Advantages
- An antibiotic-free option for treating bacterial vaginosis.
- Acts locally in the vagina with very little absorbed into the rest of the body.
- A short, self-applied course that suits many people.
Disadvantages
- Should be avoided during a period, which can make timing awkward.
- Treats bacterial vaginosis but not thrush, which it can be confused with.
- Recurrent or pregnancy-related BV still needs clinical assessment.
Practical use
Good to know
Dequalinium is placed high into the vagina, usually at bedtime so it dissolves and stays in place overnight. It should be avoided during a period, as menstrual bleeding can wash it out and reduce how well it works; treatment is best timed to avoid this. It treats bacterial vaginosis, not thrush, and the two can be confused, so if you are unsure which you have it is worth checking with a pharmacist or clinician. BV that keeps coming back, or that happens in pregnancy, should be assessed rather than repeatedly self-treated.
Who should not take it / use with caution
- People who have had an allergic reaction to dequalinium.
- Those who are not sure whether they have BV or thrush, as the treatments differ — check first.
- Pregnant or breastfeeding women, and anyone with recurrent BV or other symptoms, should seek advice rather than self-treat.
Monitoring
- No routine monitoring for a single, simple course.
- Review if symptoms do not settle or keep coming back.
- A clinical check is advised in pregnancy or recurrent bacterial vaginosis.
Side effects
- Often none; sometimes mild local irritation, itching or discharge where it is used.
- Occasional redness or soreness of the surrounding skin.
- Rarely, an allergic reaction with marked swelling or rash — stop and seek advice if this happens.
Key interactions
- Soaps, vaginal washes and douches can reduce its effect, so avoid them during the course.
- Spermicides and some other vaginal products may interfere with it.
- Very little is absorbed, so interactions with tablets taken by mouth are unlikely.
Available as: Vaginal tablet inserted into the vagina.
Answers
Dequalinium: frequently asked questions
What is bacterial vaginosis and how is it different from thrush?
Bacterial vaginosis is an imbalance of vaginal bacteria that often causes a thin, greyish, fishy-smelling discharge, whereas thrush is a yeast infection that typically causes itching and a thick white discharge. They need different treatments, so it helps to be sure which you have before treating.
Can I use dequalinium during my period?
It is best avoided during a period, because menstrual bleeding can wash the tablet out and make it less effective. Time the course so it does not overlap with your period, and ask a pharmacist if your period starts unexpectedly mid-treatment.
Is dequalinium an antibiotic?
It is a vaginal antibacterial that works as an antiseptic-type agent inside the vagina, rather than an antibiotic taken by mouth. It offers an alternative to antibiotic tablets or gels for treating bacterial vaginosis.
When should I see a doctor about BV?
See a clinician if you are pregnant, get BV often, have unusual bleeding or pain, are not sure of the diagnosis, or symptoms do not settle with treatment. Recurrent or uncertain symptoms need proper assessment.
Will it stop bacterial vaginosis coming back?
It treats the current episode but does not guarantee BV will not return, as the condition often recurs. Avoiding douches, perfumed washes and overly frequent vaginal cleaning can help, and persistent recurrence should be discussed with a clinician.
The wider class
About Vaginal antibacterials
Dequalinium belongs to the vaginal antibacterials class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF: Dequalinium.
- NICE CKS: Bacterial vaginosis.
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