What is Oral Yeast Infection?

Oral yeast infection, or thrush, is a mouth infection caused by Candida fungus.  Though oral yeast infection can affect anyone regardless of age, thrush is most common in babies, toddlers, the elderly, and people with compromised immune function.  In most cases, yeast harmlessly populates people’s skin, mouth, and gastrointestinal tract, without ill effect.  While we all have yeast cells in our bodies, natural bacteria and other immune factors work to keep yeast in check.  When this natural balance is upset, an overgrowth of yeast can result in an oral yeast infection.

Predisposing Factors

Some of the factors that predispose people to oral yeast infections are illness, stress, and medications – in particular antibiotics and hormonal birth control.  Illnesses like diabetes, cancer, and HIV cause decreased immune function, predisposing people to oral yeast infections.

Mothers and Babies

Newborn babies are particularly susceptible to oral yeast infections.  In breastfed babies, the infection may be passed back and forth from baby to mother, and vice versa.  For this reason, it’s important to treat both mother and baby to avoid continued cross contamination.  Oral yeast infections in babies travel through the body via the gut, and may cause gastrointestinal distress as well as raised, red diaper rash.  Breastfeeding mothers of babies with oral thrush may experience soreness, redness, and discharge from the breasts.  Once an oral yeast infection is well established in a baby, the infection often thrives in the moist mucosal tissues, especially since it comes into continuous contact with and feeds off of the sugars in breastmilk or formula.

Symptoms of Oral Yeast Infection

Symptoms of oral thrush may occur quite suddenly and may last over a long period of time.  The primary symptom of oral yeast infection is patches of creamy, white lesions in the mouth that look like and have the consistency of curds of cottage cheese.  When these patches are scraped from the mouth, they typically reveal red or even slightly bloody tissue beneath.

Spread of Infection

In the most extreme cases, the infection spreads to the esophagus causing pain, difficulty swallowing, and a sensation of food being stuck in the esophagus.  Oral yeast infection provides a direct route for the fungus to travel through the intestinal tract, which may result in abdominal cramping, pain, and diarrhea.  The yeast organism can also be aspirated into the lungs, resulting in lung infection and respiratory problems.  These types of cross infection are quite rare, since in most cases oral thrush does not cause life threatening symptoms and can be effectively treated. Generalized infection and spreading of the acute infection to other organs and tissues is more common in severely immunocompromised people.

Treatments

Treatment of oral yeast infections usually involves prescription antifungal medications, in the form of tablets, liquids, or lozenges.  When oral yeast infection spreads to the skin, as in the case of yeast diaper rash, the secondary infection is typically treated with nystatin or another anti-fungal cream.

Prevention

Strategies for preventing oral thrush or avoiding its recurrence include good hygiene oral hygiene habits and avoidance of mouthwashes or antiseptic sprays.  These can actually kill friendly bacteria that help keep yeast in check.  Limiting intake of sugars and yeast containing foods like breads and fermented alcohol is another important prevention strategy.  In nursing mothers and babies, it’s important to keep the breasts clean and dry, and not to allow breastmilk or formula to pool in the baby’s mouth or underneath the chin.  Prevention strategies are particularly important for people who know they are susceptible to oral thrush due to weakened immune function.