Thrush is a fungal infection of the oral * cavity. It usually manifests as raised white patches in the mouth and throat that may have the appearance of cottage cheese. The infection is usually caused by a candida fungus (a fungus of the genus Candida), of which Candida albicans is the most common. Candida is also the type of fungus that causes most diaper rash and vaginal yeast * infections. Thrush may also be caused by a fungus of the genus Monilia.

A person with thrush might have raised white patches on the tongue caused by Candida albicans.

A person with thrush might have raised white patches on the tongue caused by Candida albicans.

What Is Thrush?

Thrush is an oral fungal infection. The most common causative agent, C. albicans, is a single-celled fungus (single-celled fungi, or yeasts, reproduce by budding) that is a natural inhabitant of the mouth. Usually, the body maintains a natural balance of microbes * in the mouth. If that natural balance has been disturbed, however, Candida and other fungi may begin to grow in the warm, moist environment of the mouth and throat. Other names for thrush are oral candidiasis (kan-di-DY--a-sis) and oral moniliasis (mon-i-LY--a-sis).

Thrush and the immune system

Thrush is common in newborns. In older children and adults, it may be a sign of an immune system * disorder. People whose immune systems have been damaged by HIV * (human immunodeficiency virus), the virus that causes AIDS * , for example, may develop thrush because a properly functioning immune system is needed to maintain the natural balance of microbes in the mouth. Others at risk for thrush include individuals who are treated with antibiotics * for bacterial infections and people who use steroid inhalers for asthma * .

Neonatal thrush

Infants may become infected during the birth process if their mothers have vaginal yeast infections, or they may get thrush from bottles or rubber nipples that have not been handled carefully or from a family member or caregiver whose hands have been poorly washed. Thrush usually appears as whitish, smooth (even velvety) patches on the tongue, palate (roof of the mouth), inner cheeks, or throat. The whitish patches should not be scraped because this will hurt the infant and leave behind an inflamed and possibly bleeding area, and infants may refuse to suck because of pain in the mouth. Candida also causes diaper rash, but the rash is reddish rather than white.

How Is Thrush Diagnosed and Treated?

A doctor can almost always diagnose thrush just by looking at the mouth and tongue. If uncertain, however, the doctor may perform a culture of one of the lesions. Thrush may be a sign of an immune system deficiency, and people with thrush or with suspected thrush should visit a doctor or dentist, who will be able to identify the yeast under a microscope if necessary, check for possible causes, and suggest ways to prevent its recurrence. For thrush in neonates and infants, treatment is often unnecessary. Doctors usually treat thrush with antifungal drugs *

In some people, thrush may progress to a full systemic disease, which is generally severe. This includes persons with HIV/AIDS, persons receiving chemotherapy * or immunosuppressant drugs, or persons with some other immune system disorder. The treatment for this type of often-severe candidiasis is intravenous * antifungal medication, which is administered in a hospital setting.

See also AIDS and HIV Infection • Fungal Infections • Immune Deficiencies • Immune System and Other Body Defenses: Overview • Mouth Disorders: Overview


Books and Articles

Kalyoussef, Sabah. “Pediatric Candidiasis.” Medscape, June 17,2015. (accessed November 17, 2015).

Kumar, Mudra. “Thrush.” Medscape, June 17, 2015. (accessed November 17, 2015).

Schubert, Mark, and David H. Spach. “Oral Candidiasis.” HIV Web Study, March 27, 2015. (accessed November 17, 2015).


MedlinePlus. “Thrush.” U.S. National Library of Medicine. (accessed November 17, 2015).

NHS Choices. “Oral Thrush in Babies.” National Health Service. (accessed November 17, 2015).

Office of Women's Health. “Oral Candidiasis (Thrush).” U.S. Department of Health and Human Services. (accessed November 17, 2015).


American Association of Oral and Maxillofacial Surgeons. 9700 West Bryn Mawr Ave., Rosemont, IL 60018-5701. Toll-free: 800-822-6637. Website: (accessed November 17, 2015).

American Dental Association. 211 East Chicago Ave., Chicago, IL 60611-2678. Telephone: 312-440-2500. Website: (accessed November 17, 2015).

Centers for Disease Control and Prevention. 1600 Clifton Rd., Atlanta, GA 30329-4027. Toll-free: 888-674-6854. Website: (accessed November 17, 2015).

* oral means by mouth or referring to the mouth.

* yeast (YEEST) is a general term describing single-celled fungi that reproduce by budding.

* microbes (MY-krobes) are microscopic living organisms, such as bacteria, viruses, and fungi.

* immune system (im-YOON SIStem) is the system of the body composed of specialized cells and the substances they produce that helps protect the body against disease-causing germs.

* HIV, or human immunodeficiency virus (HYOO-mun ih-myoono-dih-FIH-shen-see), is the virus that causes AIDS (acquired immunodeficiency syndrome).

* AIDS, or acquired immunodeficiency (ih-myoo-no-dih-FIH-shensee) syndrome, is an infection that severely weakens the immune system; it is caused by the human immunodeficiency virus (HIV).

* antibiotics (an-tie-by-AH-tiks) are drugs that kill or slow the growth of bacteria.

* asthma (AZ-mah) is a condition in which the airways of the lungs repeatedly become narrowed and inflamed, causing breathing difficulty.

* antifungal drugs (an-ty-FUNG-al drugs) are medications that kill fungi.

* chemotherapy (KEE-mo-THER-apee) is the treatment of cancer with powerful drugs that kill cancer cells.

* intravenous (in-tra-VEE-nus), or IV, means within or through a vein. For example, medications, fluid, or other substances can be given through a needle or soft tube inserted through the skin's surface directly into a vein.

  This information is not a tool for self-diagnosis or a substitute for professional care.