Yeast infections

What is yeast infection?

Yeast infection is caused by a fungus. Certain types of yeast may be harmless in the mouth, bowels, vagina, and skin. Under certain conditions, an overgrowth of yeast can happen. This may cause itching and burning in the vagina and on the outer parts of the genitals (vulva).

Yeast is often not sexually transmitted. Male partners often do not need treatment, unless they have symptoms.

What are signs of yeast?

Signs can be very mild to severe. Some signs are:

  • Itching and/or burning
  • White, thick, clumpy discharge
  • If an odor is present, it is often not unpleasant
  • Vulvar redness and swelling
  • Discomfort during or after intercourse
  • Pain or burning when urinating

How is yeast diagnosed?

Your provider will look for common skin changes of the vulva and vagina.

A sample of your vaginal discharge can be:

  • Examined by your provider under a microscope
  • Sent for testing to diagnose a yeast infection
  • Sometimes a culture is needed to make the diagnosis

There are other types of vaginal and vulvar problems that can also cause itching, burning, and discharge. So, you need to see a provider to make a correct diagnosis. They will talk with you about the treatments that will work best for you.

What causes yeast?

A healthy vagina has many organisms (bacteria and yeast) that live together in normal balance. If the balance is upset, yeast can overgrow.

Yeast overgrowth can be caused by:

Antibiotic use

  • Certain antibiotics kill normal and harmful vaginal bacteria.
  • Even when antibiotics are used for treatment of other illnesses, they may change the bacteria in the vagina. This leads to yeast overgrowth.


  • Diabetes raises blood sugar levels, making the body a good place for yeast to grow.
  • Yeast infections may happen often and are harder to control when blood sugars are high.

Warmth and moisture in the vaginal area

  • Yeast thrives when it is warm, humid.
  • Sweating, discharge, or not keeping the area dry (wearing a damp bathing suit or pantyhose for hours) puts you at higher risk of getting a yeast infection.


  • This removes healthy secretions and dries the surface of the vagina.
  • Normal bacteria are also washed away. This lets yeast overgrow.


Yeast infections are more common in people who are immunosuppressed due to:

  • Infection, such as HIV
  • Use of immune-suppressing medicines such as steroids or chemotherapy
  • Organ transplant medicines

Hormonal contraceptives

The risk of yeast infections may be higher in women who use contraceptives with estrogen, such as:

  • Birth control pills
  • Patch
  • Vaginal ring

How are yeast infections treated?

Many medicines can be used:

  • Most over-the-counter medicines are creams or suppositories. You often use them 1 or 2 times a day for up to 7 days.
  • Your provider may prescribe medicine to take by mouth or topical ointments.

Signs of yeast often go away within 3 to 4 days after treatment. Be sure to keep using the medicine was prescribed. If it is stopped too soon, the infection can come back.

Over-the-counter medicines can be found at your pharmacy without a prescription. Our providers suggest using Clotrimazole (Gyne-Lotrimin™ or Mycelex™). They suggest you get the 5- or 7-day treatment. This often works better than the 1- or 3-day treatment.

Talk with your provider if you are pregnant before using any over-the-counter medicine.


  • Stop using the over-the-counter product and call your provider if you still have symptoms after 7 days.
  • Call your provider if your symptoms come back after using an over-the-counter product.
  • There are many types of vaginal and vulvar problems that may cause the same symptoms. Your provider can best make a correct diagnosis and help you find the best treatment.
  • How well a medicine depends on the type of yeast.
  • Self-treatment with old or borrowed medicines is never good.

How can yeast infections be prevented?

You can lower your risk by making a few easy changes in your daily life:

  • Follow the Vulvar Skin Care Guidelines. This will help to keep body tissue healthy to resist infection.
  • Always wipe front to back after bowel movements.
  • Keep your blood sugars under control if you have diabetes.
Last reviewed: 
May 2020

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