Candidiasis (thrush)

Candidiasis (thrush)


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. It can also keep returning  this is known as recurrent (or complicated) thrush.

Read more about the symptoms of vaginal thrush.

When to see your GP

If you display the symptoms of vaginal thrush for the very first time, it is recommended that you visit a GP, especially if you experience pain.

This is because the symptoms of vaginal thrush are sometimes similar to those of a number of skin conditions and, occasionally, a sexually transmitted infection (STI). However, your GP will be able to diagnose you correctly.

Your GP can take a swab to confirm whether or not you have vaginal thrush and prescribe the most suitable medication.

If you’ve had vaginal thrush diagnosed before and you recognise the symptoms, you can go directly to a pharmacy to buy anti-thrush medication over the counter.

Find your local pharmacy here.

However, if your thrush doesn’t improve after treatment, or if you have frequent bouts (at least one every few months), you should return to your GP.

Read more about how vaginal thrush is diagnosed.

Why thrush happens

Thrush is a yeast infection, usually caused by a yeast-like fungus called Candida albicans.

Many women have Candida in their vagina without it causing any symptoms. Vaginal secretions and “friendly” vaginal bacteria keep the fungus under control. Problems arise when the natural balance in the vagina is upset and Candida multiplies.

Vaginal thrush isn’t an STI, but it can sometimes be passed on to men during sex. This means that 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. Thrush can also be triggered by sex, and this is more likely if you have trouble relaxing and producing lubrication during intercourse.

Read more about the causes of vaginal thrush and how thrush can be passed on through sex.

Treating thrush

In most cases, thrush can be easily treated with either a tablet that you take orally or anti-thrush pessaries, which are inserted into your vagina. Anti-thrush creams are also available, which you apply to the skin around the vagina to ease any soreness and itchiness. If you are using an antifungal tablet, you may prefer to use an ordinary emollient (moisturiser) near your vagina, as antifungal creams can sometimes cause irritation.

Anti-thrush remedies are available either on prescription from your GP or over the counter from a pharmacy.

Treatment works well for most women, and vaginal thrush usually clears up within a few days.

However, about 1 in 20 women may have recurrent thrush (4 or more episodes in a year). Around 1 in 100 women may have thrush almost constantly. In these instances, longer courses of treatment, for up to 6 months, may be needed.

Read more about treating thrush.

Who gets vaginal thrush?

Vaginal thrush is very common. Around three-quarters of women will have a bout of thrush at some point in their lives. 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 particularly prone if you:

Read more about how to prevent vaginal thrush.

Thrush in pregnancy

You are more at risk of getting thrush while you’re pregnant.

There is no evidence that thrush affects your chances of getting pregnant. It’s important to note that if you have thrush while pregnant, it won’t harm your unborn baby.

However, if you’re pregnant or breastfeeding and you have thrush, you should avoid taking oral anti-thrush treatments. Instead, use intravaginal cream or pessaries, plus an anti-thrush cream if necessary.

Read more about thrush treatments in pregnancy.

Symptoms of vaginal thrush

The symptoms of vaginal thrush are usually obvious, but some people may not be aware they have thrush.

Typical symptoms include:

  • itching and soreness around the entrance of the vagina
  • pain during sex
  • a stinging sensation when you urinate
  • vaginal discharge, although this isn’t always present; the discharge is usually odourless and it can be thin and watery, or thick and white like cottage cheese

Severe symptoms

As well as the above symptoms, you may also have:

  • a red and swollen vagina and vulva
  • cracked skin around the entrance of your vagina 
  • sores in the surrounding area – this is rare, but it may indicate the presence of another condition, such as the herpes simplex virus (which causes genital herpes)

Complicated or uncomplicated thrush

Doctors sometimes refer to “uncomplicated” or “complicated” thrush depending on your symptoms, whether you have any other medical conditions and how often you get the yeast infection.

Uncomplicated thrush is mild thrush that you’ve had either for the first time or not very often. Complicated thrush refers to severe thrush that keeps coming back (when you’ve had four or more episodes in a year). In rare cases, complicated thrush also includes chronic infection with other yeasts. The most common example is called Candida glabrata.

When to visit your GP

Always visit your GP if:

  • this is the first time you’ve had thrush
  • you’re under the age of 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) and believe it has returned
  • you’ve reacted badly to an antifungal treatment in the past, or it didn’t work
  • your symptoms don’t improve after 7-14 days

Read about how thrush is diagnosed.

Causes of vaginal thrush

Vaginal thrush is a yeast infection that is usually caused by a type of fungus that lives naturally in the vagina.

Over 90% of cases of thrush are caused by 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 believed that a change in the natural balance of the vagina leads to the growth of Candida and causes the symptoms of thrush.

This can be a chemical change  for example, when you take antibiotics – or it can be a hormonal change  such as during pregnancy. 

What increases your chances of thrush?

Your risk of developing thrush increases if you:

  • take antibiotics
  • are pregnant
  • have poorly controlled 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 chances of developing thrush, but for you to develop the yeast 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, increase your chances of developing thrush and make it more likely 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 by having regular insulin injections and maintaining a healthy, balanced diet.

If you have poorly controlled diabetes – when your blood glucose levels go up and down, rather than being stable  you are 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 are having 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.

Read about how thrush is diagnosed.

Diagnosing vaginal thrush

In most cases, vaginal thrush is easily diagnosed.

There are several places you can go for advice and testing, including:

  • your GP surgery
  • a genitourinary medicine (GUM) or sexual health clinic
  • some contraception clinics and young people’s services

If vaginal thrush has been diagnosed before and you recognise the symptoms, you can also go directly to a pharmacy to buy anti-thrush medication over the counter.

You will be asked some questions about:

  • your symptoms
  • whether you’ve had thrush before
  • whether you’ve already used any over-the-counter medications to treat thrush
  • whether you’re prone to developing thrush – for example, if you’re taking antibiotics for another condition

You’re likely to have thrush if you have the typical symptoms of vaginal thrush, such as vulval itching and a thick, creamy discharge. 

Further tests

In some cases, further testing may be necessary. For example, if:

  • you’ve already used anti-thrush treatment but it hasn’t worked 
  • thrush keeps returning
  • your symptoms are particularly severe
  • you may have a sexually transmitted infection (STI)

Some tests you may have to undergo are described below.

Vaginal swab

A vaginal swab is similar to a cotton bud and is used to take a sample of the secretion from inside your vagina. It is then sent to a laboratory to be analysed.

The results will show whether you have a yeast infection and, if these tests are included, whether your symptoms are being caused by an STI, such as trichomoniasis.

A vaginal swab can also establish the type of fungus that is causing your thrush, but this is not a routine test.

Blood test

You may have a blood test to check whether you have a condition that increases your risk of developing thrush.

For example, the level of glucose in your blood may be tested if you’re suspected of having diabetes. If there is any possibility, you may also have a test for HIV.

If you have diabetes, you will probably have other symptoms, such as increased thirst, and you may urinate more often.

pH level

Testing the pH (acid/alkaline balance) of your vagina may be needed if the treatment doesn’t work and 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 4-4.5 is normal. A pH above 4.5 may be a sign of a common vaginal infection called bacterial vaginosis.

Read about how thrush is treated.

Treating vaginal thrush

For mild vaginal thrush, a short course of anti-thrush medicine may be recommended. It is usually taken for one to three days.

If your thrush symptoms are more severe, you’ll need to take the treatment for longer.

Anti-thrush medicines are available as:

  • an anti-thrush pessary  to deal with Candida in the vagina. A pessary is a specially shaped pill that you insert into your vagina using an applicator, similar to how a tampon is inserted
  • an anti-thrush cream  to deal with Candida on the skin around the vagina’s entrance
  • anti-thrush tablets  which can be used instead of creams and pessaries; these are swallowed 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 regardless of the type of medication they use. 

Deciding on the type of treatment

Many women use anti-thrush pessaries and creams to treat a straightforward bout of thrush. Pessaries and creams are recommended if you’re pregnant or breastfeeding.

Oral treatments are simpler and more convenient than pessaries and creams, but they can have side effects. Both are equally effective.

Anti-thrush tablets

The two main types of anti-thrush tablets that are prescribed by doctors to treat vaginal thrush contain the antifungal medicines fluconazole or itraconazole. If you prefer to use a cream, you can use an emollient moisturiser rather than an antifungal cream.

Anti-thrush tablets can cause side effects, including:

Anti-thrush pessaries

Pessaries that are often prescribed for thrush include the anti-fungal medicines:

  • clotrimazole
  • econazole
  • miconazole

Vaginal pessaries are not absorbed into the body, but they can:

  • be awkward to use
  • cause a mild burning sensation, slight redness or itching
  • leave a white or creamy stain on your underwear (it washes out)
  • damage latex condoms and diaphragms, so you will have to use another form of contraception while using them

You shouldn’t use vaginal pessaries without seeing a doctor. Read more about why vaginal pessaries should not be used frequently.

Pharmacy anti-thrush treatments

Some tablets, creams and pessaries to treat vaginal thrush are available over the counter from your pharmacist, and a prescription is not needed.

Anti-thrush pessaries and creams containing clotrimazole are widely sold from pharmacies under the brand name Canesten.

Fluconazole is also available over the counter from pharmacies as a single-dose tablet for treating thrush, under the brand names Diflucan and Canesten Oral.

These treatments can be effective if you’ve had thrush before. However, don’t buy medication directly from a pharmacy if it’s your first bout of thrush. Visit your GP first.

You shouldn’t use over-the-counter thrush treatments for a long period of time without talking to your GP.

Advice if you’re pregnant or breastfeeding 

If you have thrush and you’re pregnant or breastfeeding, you should always visit your GP rather than buying anti-thrush medication directly from a pharmacy.

You won’t be prescribed oral treatment because it may affect your baby. An anti-thrush pessary  such as clotrimazole, econazole or miconazole  will usually be prescribed.

If you’re pregnant, take care when inserting a pessary as there’s a small risk of injuring your cervix (neck of the womb). To reduce the risk, insert the pessaries using your finger instead of using the applicator.

If you have symptoms around your vulva, such as itching and soreness, you may also be prescribed an anti-thrush cream. Between attacks you may also want to use a regular moisturiser around the vagina. For example, E45 cream can be used as a soap substitute. After applying, wash it off then apply a greasier moisturiser to protect the skin. However, be aware that moisturisers can weaken condoms.

Complementary therapies

Some women find that complementary therapies, such as bathing the genital area with diluted tea tree oil gel or plain bio-live yoghurt, ease the symptoms of thrush.

However, tea tree essential oil can sometimes irritate the skin. You should not use more than one or two drops in the bath, and if there is any irritation, stop using the oil and wash the area with clean, warm water.

Although using yoghurt won’t do you any harm, there’s no evidence to suggest that it will relieve the symptoms of thrush or help treat it. It should not be considered as the main treatment method.

If you want to try using plain live yoghurt, one method is to smear it directly over the vulva to ease any soreness or irritation, and then insert it directly into the vagina.

The easiest way to do this is to use a tampon with an applicator. Push the tampon back inside the applicator, add about one teaspoon of plain live yoghurt to the space and insert the tampon in the usual way. Remove the tampon an hour later. 

Complications of vaginal thrush

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. If your symptoms don’t clear up within 7-14 days, the treatment hasn’t worked.

There are several reasons why this happens. You may 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. 

When thrush keeps coming back

If you have yeast infections that keep returning, your GP may run more tests to confirm the diagnosis and rule out other conditions. They may suggest trying a longer course of anti-thrush treatment or they may give you a prescription you can use whenever the symptoms return.

Research has suggested that a strategy known as “maintenance therapy” is effective. This involves taking an anti-thrush oral treatment or pessaries on a weekly basis for up to six months. Maintenance therapy will stop symptoms of thrush during treatment and allow the underlying causes to settle down.

Depression and sexual problems

Depression and psychosexual problems, often related to anxiety about having sex and the effect on your relationship, can sometimes develop if you have recurrent thrush.

You may wish to discuss with your partner whether tightness and dryness during sex are contributing to recurrent thrush. Your GP can advise you about specialist treatments, such as counselling

You could also try using a water or silicone-based lubricant during sex. These are available from pharmacies without a prescription.

More information and advice about sexual health problems are available in our sections on good sex and sexual health.

Male thrush

Occasionally, male partners of women who have thrush can develop a condition called candidal balanitis, where the head of the penis becomes inflamed.

If this happens, antifungal medication will usually be recommended.

Read about how to prevent thrush

Preventing vaginal thrush

If you’re prone to getting thrush, there are a number of self-help techniques you can use.

To reduce your risk of developing vaginal thrush:

  • wash your vaginal area with water and avoid using perfumed soaps, shower gels, vaginal deodorants or douches
  • use a regular moisturiser (emollient), such as E45 cream, as a soap substitute, then apply a greasier moisturiser to protect the skin. However, be aware that moisturisers can weaken condoms
  • avoid using latex condoms, spermicidal creams or lubricants if they irritate your genital area
  • avoid wearing tight-fitting underwear or tights
  • ask for thrush treatment if you are prescribed antibiotics and have had thrush before
  • try to discuss any sexual issues with your partner  for example, if you are not relaxed or lubricated enough during sex

Some women eat plain live yoghurt or take probiotic supplements to try and prevent vaginal thrush. However, there’s no firm evidence to suggest this works.