Oral thrush: A fungal infection is often the cause of these changes

Numerous bacteria and fungi live in the mouth, which normally keep each other in balance. One of the most common yeasts is Candida albicans. This fungus does not cause any symptoms as long as the immune system is intact and the oral flora remains undisturbed. However, if this balance is disrupted, the fungus can multiply rapidly. This results in whitish coatings and inflammation of the oral mucosa. The condition is therefore usually not caused by an infection, but by the excessive proliferation of yeast fungi that are already present. 

Oral thrush often develops when the body’s immune system is weakened or the oral flora is disrupted.

The most common risk factors include:

• Antibiotic therapy
• a weakened immune system
• Diabetes mellitus
• ill-fitting dentures
• Cortisone sprays for asthma
• Dry mouth
• Chemotherapy
• Infancy
• Older adults

After using a cortisone-containing asthma spray, the mouth should be rinsed thoroughly. This can significantly reduce the risk of oral thrush. 

The most noticeable symptom is a whitish coating on the tongue, the inside of the cheeks, or the roof of the mouth. This coating can often be scraped off, revealing a reddened, slightly bleeding mucous membrane underneath.

Typical symptoms include:

• white patches in the mouth
• reddened oral mucosa
• Burning sensation in the mouth
• Pain when eating
• Altered sense of taste
• Dry mouth
• Unpleasant taste
• Difficulty swallowing

In infants, it is often noticeable that they feed restlessly or refuse to feed at all. 

White lesions in the mouth can have various causes. They may also be harmless coatings, pressure sores caused by dentures, or other conditions affecting the oral mucosa. A dental or medical examination should only be sought if the lesions persist for several days or if pain develops.

In many cases, a visual examination of the oral mucosa is sufficient. The doctor assesses the appearance and extent of the patches as well as any possible underlying conditions. If the diagnosis is unclear, a swab may also be taken. Laboratory testing can determine which fungus is causing the infection and which treatment is appropriate. 

Oral thrush is usually treated with antifungal medications. These are available as oral gels, solutions, or lozenges and act directly on the oral mucosa. It’s also important to address any underlying causes. Dentures should be thoroughly cleaned. After using corticosteroid-containing inhalation sprays, it is recommended to rinse your mouth.

Treatment should be continued consistently until completion—even if symptoms subside earlier. 

Careful oral hygiene supports healing and helps prevent recurrent infections. Simple measures help stabilize the oral flora and reduce the risk of recurrent oral thrush.

Helpful measures include:

• Brushing your teeth regularly
• Thoroughly cleaning dentures
• Rinsing your mouth after using cortisone sprays
• Drink plenty of fluids
• Consuming sugary foods only in moderation
• Replace your toothbrush after the infection has cleared up 

Oral thrush is a common fungal infection of the oral mucosa that usually manifests as white patches and an unpleasant burning sensation. With the right treatment, the infection usually clears up completely. If symptoms persist or recur, the cause should be investigated by a doctor.