15 min read

Candidiasis (thrush)

Medically reviewed

All of Healthily's articles undergo medical safety checks to verify that the information is medically safe. View more details in our safety page, or read our editorial policy.

What is 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 and it can keep coming back, which is known as recurrent thrush.

Read more about the symptoms of vaginal thrush.

It is also possible for men to have thrush. Find about more about the symptoms of thrush in men.

When to see your doctor

It makes sense to see your doctor 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 (STI). Your doctor will be able to tell the difference.

Your doctor 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.

Find your local pharmacy here.

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

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. Hormones in 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 a sexually transmitted infection but it can sometimes 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 and [how thrush can be passed on through sex].

Treating thrush

Thrush can usually be easily treated with either a tablet that you take by mouth or anti-thrush pessaries that you insert into your vagina. Anti-thrush creams are also available that you can apply to the skin around the vagina to ease any soreness and itchiness.

Anti-thrush remedies are available either on prescription from your doctor 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 (four 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 six 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. 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 to it if you:

  • are pregnant
  • take antibiotics
  • have diabetes
  • have a weakened immune system

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. And, if you have thrush while you are 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 vaginal pessaries, plus an anti-thrush cream if necessary.

Read more about thrush treatments in pregnancy.

Thrush symptoms

The symptoms of vaginal thrush are usually obvious.

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

In addition to 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 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 yeast infection.

Uncomplicated thrush is mild thrush that you've had for the first time, or where you haven't had it very often. Complicated thrush refers to severe thrush that keeps coming back (where you've had four or more episodes in a year).

When to visit your doctor

Always visit your doctor if:

  • this is the first time that you've had thrush
  • you're under 16 years of age or over 60
  • you're pregnant or may be pregnant
  • you're breastfeeding
  • you have abnormal menstrual bleeding or a 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 7-14 days

Read about how thrush is diagnosed.

Thrush causes

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

Most cases of thrush (80-90%) 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 thought that there has to be a change in the natural balance of the vagina that leads to an explosion in the growth of Candida and 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 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 – that is, your blood glucose levels go up and down rather than staying 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.

Thrush diagnosis

Vaginal thrush can usually be easily diagnosed.

If you visit your doctor because you think that you may have vaginal thrush they will ask you 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

It is likely that you have thrush if you have the typical symptoms of vulval itching and a thick, creamy discharge. However, you may need to have further tests to be absolutely sure of the diagnosis.

Further tests

Your doctor may want to carry out some further tests 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)

Some possible tests are described below.

Vaginal swab

A vaginal swab is similar to a cotton bud. It is used to take a sample of the secretion from inside your vagina so that it can be analysed in a laboratory.

The results of the analysis will show whether you have a yeast infection or 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.

Blood test

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

For example, your doctor may test the level of glucose in your blood if they think you might have diabetes.

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

pH level

Testing the pH (acid/alkaline balance) of your vagina may be recommended if the treatment for thrush hasn't worked and it 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.

Thrush treatment

For mild vaginal thrush, a short course of anti-thrush medicine may be recommended. It is usually taken for between one and 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 lump of medication that you insert into your vagina using an applicator, in a similar way to how a tampon is inserted
  • an anti-thrush cream to deal with Candida on the skin around the entrance to the vagina
  • anti-thrush tablets, 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 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. They tend to only be used for troublesome thrush that keeps coming back.

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]&medicine=Sporanox&preparation=Sporanox%20100mg%20capsules).

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 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 will have to use another form of contraception while using them

You shouldn't use vaginal pessaries too often. 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 without a prescription.

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

Flucanozole is also available over the counter from pharmacies as a single-dose tablet for treating thrush under the brand name Diflucan.

These treatments can be useful for treating thrush if you've had it before and it's returned. However, avoid buying thrush medication direct from a pharmacy if it's your first bout of thrush. Visit your doctor first.

Also, you shouldn't continue to use over-the-counter thrush treatments over a long period of time without consulting your doctor.

Advice if you're pregnant or breastfeeding

If you have thrush and you're pregnant or breastfeeding, you should always visit your doctor 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. An anti-thrush pessary, such as clotrimazole, econazole or miconazole will probably be prescribed 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 (neck of the womb). To reduce the risk, it may be better to insert the pessaries by hand 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.

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 helps to ease their thrush symptoms.

However, tea tree essential oil can sometimes cause skin irritation. 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 and it should not be considered a main treatment.

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.


If you're prone to getting thrush, there are a number of self-help techniques you can try to help prevent it coming back.

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
  • avoid using latex condoms, spermicidal creams or lubricants if they irritate your genital area
  • avoid wearing tight-fitting underwear or tights
  • wear cotton underwear and loose-fitting trousers and skirts

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

Complications of 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. You can tell if 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 an abnormal vaginal discharge.

You should visit your doctor if your treatment doesn't work. They may run further tests to confirm your diagnosis and offer you some alternative treatment.

When thrush keeps coming back

If you have recurrent yeast infections, your doctor may run further 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.

Some research has suggested that a strategy known as 'maintenance therapy' can help reduce the reccurrence 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 reccurrence of thrush during treatment. It may also help to protect against thrush after treatment has stopped.

Depression and sexual problems

Depression and psychosexual problems, such as anxiety about having sex, can sometimes develop if you have recurrent thrush. Your doctor will be able to advise you about specialist treatments, such as counselling.

Male thrush

In rare cases, male partners of women who have thrush can develop a condition called candidal balanitis, which is where the head of the penis (glans) becomes inflamed.

In these cases, a course of antifungal medication will usually be recommended.

Read about how to prevent thrush.

Content supplied byNHS Logonhs.uk
Was this article helpful?

Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.