What Causes Thrush in Adults?

Reviewed on 2/25/2021

What is thrush?

Thrush in adults is caused by an overgrowth of the yeast Candida Albicans that can be caused by diabetes, medications, radiation or chemotherapy, immune system disorders, and some oral health conditions.
Thrush in adults is caused by an overgrowth of the yeast Candida Albicans that can be caused by diabetes, medications, radiation or chemotherapy, immune system disorders, and some oral health conditions.

Thrush is a fungal infection that occurs in your mouth and throat. Under normal conditions, your body contains millions of yeast and fungi. They usually cause no harm and can be beneficial and help fight disease. A particular type of yeast, called Candida albicans, normally lives in your body without causing any problems. The other beneficial bacteria in your body keeps it from causing problems.

When the conditions inside your body change, because of medication or a weakened immune system, it can lead to the yeast growing out of control and causing thrush. Thrush is not normally an issue in a healthy body. It occurs most often in people who have a weakened immune system or are taking certain medications that kill off good bacteria.

Symptoms of thrush in adults

Thrush infections can have any of the following symptoms:

  • Loss of taste
  • Cottony feeling in your mouth
  • White patches in your mouth, tongue, or throat
  • Pain with eating and swallowing
  • Cracking and redness at the corners of your mouth

Types of thrush in adults

Pseudomembranous form

This is the most common form of thrush. It is characterized by white patches on your mouth, tongue, or the back of your throat.

Atrophic form

This is a less common form of thrush that usually occurs in older adults. It appears underneath upper dentures in the form of red patches.

Causes of thrush in adults

Thrush is caused by an overgrowth of the yeast Candida Albicans. Candida is always present on the skin and inside the body in the mouth, throat, gut, and vagina. This normally does not cause any problems since the beneficial bacteria in your body keeps it from growing out of control.

However, if the environment in your mouth changes for any reason, it can lead to a fungal overgrowth. Some things that can lead to this include:

  • Medications that reduce the number of beneficial bacteria in your body such as antibiotics, inhaled corticosteroids, and prednisone
  • Radiation or chemotherapy treatments that kill healthy cells in your body
  • Conditions that weaken your immune system, including HIV/AIDS, organ transplant, or leukemia
  • Diabetes that is untreated or uncontrolled results in a lot of sugar in your saliva which encourages the growth of candida
  • Oral conditions, including wearing dentures or having a dry mouth for any reason

When to see the doctor for thrush in adults

If you have any of the symptoms of thrush, particularly white patches in your mouth, see your doctor. Thrush will need to be treated with medication.

Diagnosing thrush in adults

Your doctor will take a medical history and do a physical exam. You will be asked about any medical conditions you have and any medications you are currently taking. It's likely that a diagnosis can be made with only an exam.

However, your doctor may do a biopsy by taking a small sample from your mouth or throat. If your doctor suspects you have thrush in your esophagus, you may need to have an endoscopy.

An endoscopy is a procedure that lets your doctor see your upper digestive tract with a light and a camera on a tube.

QUESTION

What causes tooth decay? See Answer

Treatments for thrush in adults

The treatment your doctor chooses for thrush will depend on how severe it is, your age, and other medical conditions you may have. Your doctor will want to treat your thrush as early as possible to prevent it from spreading and to ease the pain.

Antifungal medications are the standard treatment for thrush. Your doctor may prescribe a liquid that you swish around in your mouth and then swallow, or a lozenge. If your thrush is resistant to this type of medicine, you may need to take an antifungal medication in a pill form.

The following home remedies may help as well:

  • Brush and floss twice a day.
  • Replace your toothbrush after your thrush clears up.
  • Disinfect your dentures to avoid reinfecting yourself.
  • Rinse your mouth with warm saltwater using one teaspoon of salt dissolved in one cup of water.
  • Avoid using mouthwash unless your doctor has prescribed it.

Preventing thrush

Thrush will generally clear up once you start treatment, but it may return if the underlying condition goes untreated. To help prevent thrush in the future, you may want to do the following:

  • Brush and floss your teeth regularly.
  • Ask your doctor about using a chlorhexidine mouthwash.
  • Clean and disinfect your dentures regularly, and make sure they fit well.
  • Rinse your mouth thoroughly after using a corticosteroid inhaler.
  • Only use antibiotics if absolutely necessary.
  • Get treatment for underlying conditions that make you vulnerable to thrush, such as diabetes.

Health Solutions From Our Sponsors

References
Centers for Disease Control and Prevention: "Invasive Candidiasis."

Centers for Disease Control and Prevention: "Candida Infections of the Mouth, Throat, and Esophagus."

Cedars-Sinai: "Candida Infection: Thrush."

Merck Manual: "Candidiasis: Yeast Infection."

Mayo Clinic: "Oral Thrush."

Health Solutions From Our Sponsors