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Quick Facts

Candidiasis (Yeast Infection)


The Manual's Editorial Staff

Last full review/revision Nov 2020| Content last modified Nov 2020
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What is candidiasis?

Candidiasis is an infection by Candida yeast. Because yeast is a type of fungus, candidiasis is a fungal infection, but it's usually referred to as a yeast infection. Candida yeast usually live on your body in small amounts without causing symptoms. But sometimes an overgrowth or infection can happen.

  • Yeast infections usually happen on the surface of your body, including your skin, mouth, or vagina

  • Sometimes people with a weak immune system get yeast infections of their internal organs (systemic candidiasis), which can be life-threatening

  • A yeast infection may cause redness, rash, itching, swelling, or creamy white patches

  • Some diaper rashes are caused by yeast infection

  • Doctors treat yeast infections with creams or medicines taken by mouth

What causes a yeast infection?

A yeast infection is caused by Candida yeast, a fungus that usually lives on your body in small amounts. In small amounts, you don't notice it. If the yeast grows too much, you get a rash.

Some causes of too much yeast growth include:

  • Wearing tight underwear, bras, or other clothing that holds sweat close to your body

  • Keeping babies in wet or dirty diapers too long

  • Having diabetes

  • Having a weak immune system because of disorders such as HIV infection or cancer

  • Taking antibiotics

Yeast likes to live in dark, moist areas of your body. So yeast infections are more common in these areas:

  • Under folds of skin in obese people

  • In the mouth

  • Under women's breasts

  • In the groin area or vagina

What are the symptoms of a yeast infection?

Symptoms depend on where the yeast infection is:

  • On your skin: Bright red, raw rash

  • Inside your vagina: White patches and white, cheeselike vaginal discharge

  • Inside your mouth: White patches (thrush)

  • Corner of your mouth: Cracks in the skin

Yeast Infections

How do doctors tell if I have a yeast infection?

Doctor can usually tell if you have a yeast infection just by looking at it. To know for sure, doctors may scrape off a tiny bit to view under a microscope.

How do doctors treat yeast infections?

Treatment depends on where the yeast infection is.

For infections on your skin, doctors will have you:

  • Apply antifungal creams, powders, or other products to the infected area

  • Keep the skin dry (for example, by changing a baby’s diaper more often)

  • Take medicine by mouth, if the infection is severe

For a yeast infection in your vagina, doctors will have you:

  • Apply an antifungal cream inside and outside your vagina

  • Sometimes, take medicines by mouth

For thrush in adults, doctors will have you:

  • Take an antifungal medicine

  • Sometimes, gargle with liquid antifungal medicine (nystatin)

For thrush in babies, doctors will have you apply a liquid antifungal medicine to the inside of your baby’s mouth.

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