Yeast Infection Patient Information Fact Sheet

What is a yeast infection?
Yeast infection, also known as vaginal candidiasis or vaginal thrust, is an infection caused by a fungus (yeast) called Candida albicans. Candida albicans is present naturally in the intestines and vagina but in certain circumstances overgrowth of the organism may occur causing an infection. A yeast infection is not a sexually transmitted disease (STD) but it can be passed on to a sexual partner. About 75% of women have at least one episode during their lives.

What are the symptoms of a yeast infection?
All women have a natural vaginal discharge. If there are any changes in the nature of the normal discharge an infection may be present. The first time a woman has a yeast infection she will normally seek medical advice to confirm that it is in fact a yeast infection and not another type of vaginal infection. Some women suffer from recurrent a yeast infections and learn to recognize the start of symptoms very quickly.

There is usually a thick, white discharge which is often described as resembling cottage cheese. The discharge caused by a yeast infection should not smell and should not change color; if it smells or changes color this may indicate a different type of infection. The discharge may become quite heavy and can cause severe vulval itching. The vulva may become inflamed and swollen. Sexual intercourse can be very uncomfortable and it may hurt to pass urine. Although it is not a serious condition, a yeast infection can be very uncomfortable and needs treatment.

What causes a yeast infection?
A yeast infection occurs when the normal balance between the micro-organisms naturally found in the vagina is disturbed. An imbalance can be triggered by a number of things and some women are more prone to developing a yeast infection than others. Some antibiotics can kill the "friendly" bacteria as well as the harmful bacteria for which they have been prescribed. The "friendly" bacteria maintain an acidic environment in the vagina that prevents Candida albicans from multiplying. When the balance becomes upset, for example, by antibiotics, the fungus is able to multiply and a yeast infection develops. Some women may need to take a course of antifungal treatment whenever they have to take antibiotics to prevent a yeast infection from occurring.

The normal balance of micro-organisms in the vagina can also be upset during pregnancy as a result of the increase in vaginal sugar levels that may be caused by increased estrogen levels. In some women, taking the contraceptive pill can have a similar effect and will also cause a yeast infection. Some women suffer from a yeast infection before their period (premenstrual yeast infection) as menstrual blood raises the pH level of the vagina, making it less acidic and thereby disturbing the balance between the micro-organisms.

The use of scented bubble bath, soap and vaginal deodorants can irritate the vagina and trigger a yeast infection in some women. Using tampons or wearing nylon tights and underwear can cause a yeast infection to occur and some women find that a diet high in sugar can also trigger one.

Men usually only develop a yeast infection when it is passed to them by a sexual partner. The symptoms of a yeast infection in men are fairly similar to those seen in women, although some men can carry the infection without showing any symptoms at all. They may have itching or burning at the tip of the penis or under the foreskin. A thick, white discharge may also develop under the foreskin and can make it difficult to retract. They may also experience discomfort when passing urine.

If a sexual partner is not treated for a yeast infection at the same time as the sufferer, they can pass the infection back to the sufferer again. Both partners must be treated even if the male has no symptoms.

What tests confirm a diagnosis of yeast infection?
If it is the first yeast infection, your doctor  may take a culture to confirm the diagnosis. If the a yeast infection recurs, the symptoms are usually recognized and no further testing should be necessary.

How are yeast infections treated?
A yeast infection is treated with antifungal creams that are applied locally to the area surrounding the vagina or with antifungal suppositories or cream that are inserted into the vagina. Often a combination of both of these are prescribed at the same time. Examples of topical antifungal agents used to treat a yeast infection include butoconazole (Gynazole-1), clotrimazole (Gyne-Lotrimin Vaginal Cream), terconazole (Terazol 3 Vaginal Cream), tioconazole (Vagistat-1), miconazole (Monistat), and nystatin. Some treatments for a yeast infection are available to buy from a pharmacy without a prescription. Fluconazole (Diflucan) is an oral antifungal that is used to treat yeast infection.

Self-help measures

  • Eat yogurt with live, active cultures. This can increase the levels of naturally occurring bacteria known as lactobacilli, which will help to decrease the levels of Candida albicans and help to prevent recurrent yeast infections. Natural yogurt can also be applied directly into the vagina during an attack.
  • Cut down on refined sugar (eg, chocolate); this can also be beneficial.
  • Add a tablespoon of vinegar to bath water to relieve symptoms of itching.
  • Wear cotton underwear and try to avoid wearing tights or tight clothing.
  • Avoid using highly perfumed bubble baths and soaps. Use a simple soap or baby product instead.
  • Sexual intercourse during a yeast infection can be painful. However, if sexual intercourse takes place while one or both partners have a yeast infection a condom must be used until both partners have been treated to prevent reinfection.

Further information
U.S. Department of Health and Human Services: www.womenshealth.gov/publications/our-publications/fact-sheet/vaginal-yeast-infections.cfm

Last Reviewed: May 2013