Most women experience occasional bouts of a common yeast infection known as vaginal thrush.
It causes itching, irritation and swelling of the vagina and surrounding area, sometimes with a creamy white cottage cheese-like discharge.
Vaginal thrush is fairly harmless but it can be uncomfortable and it can keep coming back, which is known as recurrent thrush.
Read more about the symptoms of vaginal thrush.
When to see a doctor
It makes sense to see your GP if you have the symptoms of vaginal thrush for the very first time.
That's because the symptoms of vaginal thrush are sometimes similar to those of a sexually transmitted infection. Your doctor will know how to tell the difference.
Your GP can diagnose vaginal thrush and prescribe the most suitable anti-thrush medication for you.
If you've had diagnosed vaginal thrush before and you recognise your symptoms, you can go directly to a pharmacy to buy anti-thrush medication over the counter.
However, return to your doctor if thrush doesn't improve after treatment, or if you have frequent bouts - i.e. at least one every few months.
Read more about how vaginal thrush is diagnosed.
Why it happens
Thrush is usually caused by a yeast-like fungus called Candida albicans.
Many women have Candida in the vagina without it causing any symptoms. Hormones in the vaginal secretions and the friendly vagina bacteria keep the fungus under control. Problems arise when the natural balance in the vagina is upset and Candida multiplies.
Vaginal thrush isn't a sexually transmitted infection but it can occasionally be passed on during sex. So, if you have thrush it's best to avoid having sex until you've completed a course of treatment and the infection has cleared up.
Read more about the causes of vaginal thrush.
Thrush is usually easily treated with either a tablet that you take by mouth, or anti-thrush pessaries that you insert into the vagina. There are also anti-thrush creams that you can apply to the skin around the vagina to ease the soreness and itchiness.
Anti-thrush remedies are available either on prescription from a doctor or over-the-counter from a pharmacy.
Treatment works well for most women, and vaginal thrush usually clears up within a few days.
Around one in 20 women, however, may have recurrent thrush (four or more episodes in one year). One in 100 women may have thrush almost constantly. In these instances, longer courses of treatment, for up to six months, may be needed.
Read more about thrush treatments.
Who gets vaginal thrush?
Vaginal thrush is extremely common. Around 75% (three-quarters) of women will have an attack at some point. Up to half of these will have thrush more than once.
Thrush most commonly affects women in their twenties and thirties. It is less common in girls who have not yet started their periods, and women who have been through the menopause.
While any woman can experience a bout of thrush, you're especially prone to it if you:
- are pregnant
- take antibiotics
- have diabetes
- have a weakened immune system
Read more about what you can do to prevent vaginal thrush.
Thrush in pregnancy
You are more prone than usual to thrush while you're pregnant.
There's no evidence that thrush affects your chances of getting pregnant. And, if you have thrush while you're pregnant, it won't harm your unborn baby.
However, if you're pregnant or breastfeeding and you have thrush, you should avoid oral anti-thrush treatments. Instead, use vaginal pessaries, plus an anti-thrush cream if necessary.
- Hormones are groups of powerful chemicals that are produced by the body and have a wide range of effects.
- Immune system
- The immune system is the body's defence system, which helps to protect it from disease, bacteria and viruses.
- The vagina is a tube of muscle that runs from the cervix (the opening of the womb) to the vulva (the external sexual organs).
- A woman's external sexual organs, made up of the outer part of the vagina, the clitoris and the two pairs of lips surrounding the entrance to the vagina (the labia majora and the labia minora).
The signs of vaginal thrush are usually very obvious.
Typical symptoms include:
- itching and soreness around the entrance to the vagina
- pain during sex
- a stinging sensation when you urinate
- vaginal discharge, although this isn't always present; the discharge is usually odourless; it can be thin and watery, or thick and white, like cottage cheese
In addition to the above symptoms, you may also have:
- redness of the vagina and vulva
- cracked skin around the entrance to the vagina
- swelling of the vagina and vulva
- sores in the surrounding area (this is rare, but may indicate the presence of another fungal condition, or the herpes simplex virus - the virus that causes genital herpes)
Doctors sometimes refer to 'uncomplicated' or 'complicated' thrush depending on your symptoms and how often you get the infection.
Uncomplicated thrush refers to mild thrush where it's a first bout or you haven't had it very often before. Complicated thrush refers to severe thrush that tends to keep coming back (you've had four or more episodes in a year).
When to visit your GP
Always see your GP if:
- this is the first time you've had thrush
- you're under 16 or over 60
- you're pregnant or may be pregnant
- you're breastfeeding
- you have abnormal menstrual bleeding or blood-stained discharge
- you have lower abdominal pain
- your symptoms are different from previous bouts of thrush, for example, if the discharge is a different colour or has a bad smell
- you have vulval or vaginal sores
- you've had two cases of thrush within the last six months
- you or your partner have previously had a sexually transmitted infection (STI)
- you've reacted badly to an antifungal treatment in the past, or it didn't work
- your symptoms don't improve after 7 to 14 days
Vaginal thrush is caused by the overgrowth of a yeast-like fungus that lives naturally in the vagina.
Most cases of thrush - between 80 and 90% - are due to a type of fungus called Candida albicans.
The rest are due to other types of Candida fungi.
Up to half of women have Candida living naturally in their vagina without it causing any symptoms.
It's thought that there has to be a change in the natural balance of the vagina, which leads to an explosion in the growth of Candida that causes the symptoms of thrush.
This change can be a chemical change, such as when you take antibiotics. Or it can be a hormonal change, for instance, during pregnancy.
What increases your chances of thrush?
Your risk of developing thrush increases if you:
- take antibiotics
- are pregnant
- have diabetes
- have a weakened immune system
Thrush happens in about a third of women who take antibiotics because antibiotics get rid of the friendly bacteria in the vagina.
Any type of antibiotic can increase your risk of developing thrush. But for you to develop the infection, the Candida fungus must already be present in your vagina.
If you're pregnant, changes in the levels of female hormones, such as oestrogen, make you more likely to develop thrush and for it to keep coming back.
Diabetes is a long-term condition that's caused by too much glucose in the blood. It's usually kept under control through insulin injections or through your diet.
If you have diabetes that's poorly controlled, i.e. your blood glucose levels go up and down rather than staying stable, you're more likely to develop thrush.
Weakened immune system
Your risk of developing thrush is also increased if your immune system is weakened, for example, when you have an immunosuppressive condition, such as HIV or AIDS, or if you're receiving chemotherapy. This is because in these circumstances your immune system, which usually fights off infection, is unable to control the spread of the Candida fungus.
Vaginal thrush is usually easily diagnosed.
If you visit your GP because you think you may have vaginal thrush, your GP will ask you about:
- your symptoms
- whether you've had thrush before
- whether you've already used any over-the-counter (OTC) medications to treat thrush
- whether you're prone to developing thrush. For example, if you're taking antibiotics for another condition
Your GP can be fairly certain that you have thrush if you have the typical symptoms of vulval itching and a thick, creamy discharge. But sometimes you may need further tests to be absolutely sure of the diagnosis.
Tests for thrush
Your GP may want to perform further tests to confirm that you have thrush if:
- you've already used anti-thrush treatment but it hasn't worked
- the thrush keeps returning
- your symptoms are particularly severe
- you may have a sexually transmitted infection (STI)
Your GP can do several tests to confirm that you have thrush. They include:
- a vaginal swab
- pH test
- blood test
During this test, a swab - which is similar to a cotton bud - is used to take a sample of the secretion from inside your vagina. The sample is then analysed in a laboratory.
The sample will show whether you have thrush or whether your symptoms are being caused by a sexually transmitted infection, such as trichomoniasis.
If can also establish the type of fungus that's causing your thrush.
Testing the pH level
Your GP may want to test the pH (alkaline/acid balance) of your vagina if the treatment for your thrush hasn't worked, and your thrush keeps returning. To do this, a swab is taken from inside your vagina and wiped over a piece of specially treated paper. The paper will change colour depending on the pH level.
A pH level of between 4-4.5 is normal. A pH above 4.5 may be a sign of a common vaginal infection called bacterial vaginosis.
Your GP may test the glucose level of your blood if they suspect that you could have diabetes. This condition is caused by too much glucose in the blood. It's likely to cause other symptoms, such as increased thirst and urinating more often.
If your symptoms of vaginal thrush are mild, your GP or pharmacy may recommend a short course of anti-thrush medicine, which is usually taken for 1 to 3 days.
If your symptoms are more severe, you'll need to take the treatment for longer.
Anti-thrush treatments come as:
- an anti-thrush pessary to deal with Candida in the vagina. A pessary is a specially-shaped lump of anti-thrush medication that you insert into the vagina using an applicator that's provided in the same way as a tampon.
- an anti-thrush cream to deal with Candida on the skin around the entrance to the vagina.
- anti-thrush tablets and pills, which can be used instead of creams and pessaries. These are taken by mouth and are called oral treatments.
Pessaries and oral treatments have been found to be equally effective in treating thrush. Around 80% of women are successfully treated, whichever type of medication they use.
Which treatment should you take?
Many women use anti-thrush pessaries and creams to treat a straightforward bout of thrush. Pessaries and creams are the recommended treatment if you're pregnant or breastfeeding.
Oral treatments are simpler and more convenient than pessaries and creams, but they can have side effects. They tend to be used only for troublesome thrush that keeps coming back.
Anti-thrush tablets and pills
The two main types of anti-thrush tablets that are prescribed by doctors for vaginal thrush contain the antifungal medicines fluconazole or itraconazole.
Anti-thrush tablets can cause side effects, including:
- an upset stomach
Pessaries that are often prescribed for thrush include the anti-fungal medicines:
Vaginal pessaries don't cause as many side effects as anti-thrush tablets, but they can:
- be awkward to use
- cause a mild burning sensation, slight redness or itching
- leave a whiteish creamy stain on your underwear (it washes out!)
- damage latex condoms and diaphragms, so you have to use another form of contraception while using them
You shouldn't use vaginal pessaries too often.
Pharmacy anti-thrush treatments
Some tablets, creams and pessaries to treat vaginal thrush are available over-the-counter from your pharmacist, without a prescription.
Anti-thrush pessaries and creams containing clotrimazole are widely sold from pharmacies under the brand name Canesten.
These pharmacy treatments can all be useful for treating thrush if you've had it before and it has returned.
However, don't buy your thrush medication direct from a pharmacy if it's your first bout of thrush - see your GP first. And don't use pharmacy treatments for too long without first seeking medical advice.
Advice if you're pregnant or breastfeeding
If you have thrush and you're pregnant or breastfeeding, always visit your GP rather than buying anti-thrush medication over-the-counter from a pharmacy.
You won't be prescribed oral treatment because it may affect your baby. You are likely to be prescribed an anti-thrush pessary, such as clotrimazole, econazole or miconazole, to be used for at least seven days.
If you're pregnant, take care when inserting a pessary because there's a risk of injuring your cervix. To reduce the risk, you may prefer to insert the pessaries by hand instead of using the applicator.
If you have symptoms around your vula, such as itching and soreness, you may also be prescribed an anti-thrush cream.
The yogurt remedy
Some women claim that applying plain bio-live yogurt to the vagina helps ease thrush symptoms. Although using yogurt won't do you any harm, there's no firm evidence that it will help to banish thrush.
If you want to try yogurt, one method is to smear plain live yogurt directly over the vulva to ease any soreness or irritation, and insert it directly into the vagina. The easiest way to do this is using a tampon with an applicator. Push the tampon back inside the applicator, add about one teaspoon of plain live yogurt to the space and insert the tampon in the usual way. Then remove the tampon an hour later.
The main complications of thrush are:
- the treatment doesn't work
- the thrush keeps coming back
- depression and sexual problems
- penis problems in male partners
When thrush treatment fails to work
Anti-thrush medication fails to work in up to one in five cases. You know the treatment hasn't worked if your symptoms don't clear up within 7-14 days.
There are several reasons why treatment for thrush may not work. It may be that you have a different infection, such as bacterial vaginosis, which is the most common cause of abnormal vaginal discharge.
If your treatment doesn't work, visit your GP. They may run further tests to confirm your diagnosis and offer you some alternative treatment.
When thrush keeps coming back
If you have recurrent thrush, your GP may run further tests to confirm the diagnosis and rule out other conditions (see female thrush - diagnosis). Your GP may suggest a longer course of anti-thrush treatment, or give you a prescription that you can use whenever the symptoms return.
Some research has suggested that a strategy known as 'maintenance therapy' can reduce the recurrence of thrush. Maintenance therapy involves taking an anti-thrush oral treatment or pessaries on a weekly or monthly basis for up to six months.
Maintenance therapy has been shown to reduce the recurrence of thrush during treatment. It may also help to protect against thrush after treatment has stopped.
Depression and sexual problems
In rare cases, male partners of women who have thrush can develop a condition called candidal balanitis (inflammation of the head of the penis). If this happens, the GP usually recommends a course of antifungal medication for men with the condition.
If you're prone to thrush, there are some self-help techniques that you can try to prevent it coming back.
To reduce your risk of vaginal thrush:
- wash your vaginal area with water and avoid perfumed soaps, shower gels, vaginal deodorants, or douches
- avoid latex condoms, spermicidal creams or lubricants if they irritate your genital area
- avoid tight-fitting underwear or tights
- wear cotton underwear and loose-fitting trousers and skirts
Some women eat plain live yogurt or take probiotic supplements to try to prevent vaginal thrush, but there's no firm evidence that this works.