The presence of white patches in the mouth, sometimes described as looking like “oysters” or cottage cheese, is medically known as oral thrush (oral candidiasis). This common condition is a fungal infection caused by an overgrowth of the yeast Candida albicans, which naturally resides in the mouth and digestive tract. Normally, other microorganisms keep this yeast in check, but disruption allows the fungus to multiply rapidly. While generally not serious in healthy individuals, treatment is required to clear the discomfort and prevent spreading.
Understanding Oral Thrush Symptoms
The most recognizable symptom of oral thrush is the appearance of creamy white, slightly raised patches inside the mouth. These lesions often resemble milk curds or cottage cheese and are typically found on the tongue and the inner cheeks. The patches may also spread to the roof of the mouth, the tonsils, or the gums, sometimes joining together to form larger plaques.
If these white patches are rubbed or scraped, they may reveal red, inflamed areas underneath that can bleed slightly. Patients often report an uncomfortable “cottony” feeling in the mouth, along with redness, soreness, or a burning sensation. In severe cases, this discomfort can make eating, drinking, or swallowing difficult, and some people may experience a loss of taste. Cracking and redness, known as angular cheilitis, can also develop at the corners of the mouth.
What Causes the Overgrowth
Oral thrush develops when the body’s natural balance of microorganisms is upset, allowing Candida yeast to multiply without control. Common triggers include broad-spectrum antibiotics, which eliminate beneficial bacteria that suppress Candida growth. The use of inhaled corticosteroids for conditions like asthma can also increase the risk, especially if the mouth is not rinsed afterward.
A weakened immune system is a factor, making infants, the elderly, and individuals with chronic conditions more susceptible. Uncontrolled diabetes creates a high-sugar environment in the saliva, which serves as a food source for the yeast. Conditions causing chronic dry mouth (xerostomia) also increase vulnerability, as saliva helps control the oral flora.
Other local factors contribute to the overgrowth, such as poor oral hygiene or wearing dentures, particularly those that do not fit correctly. Dentures can trap the yeast against the moist tissues of the mouth, promoting colonization and infection. Certain medical treatments, including chemotherapy and radiation therapy for cancer, also compromise the body’s defenses, raising the likelihood of developing oral candidiasis.
Effective Treatment and Prevention Methods
Treatment for oral thrush typically involves antifungal medications to eliminate the yeast overgrowth. For mild to moderate cases, a healthcare provider may prescribe a topical antifungal, such as nystatin suspension or slow-dissolving clotrimazole lozenges. These topical treatments are usually applied for seven to fourteen days.
More severe or persistent infections may require systemic antifungal medication, such as fluconazole, taken as an oral tablet. Consult a medical professional for a proper diagnosis and prescription, as they determine the appropriate course of treatment based on severity and overall health. Delaying care can lead to the infection becoming more widespread.
To prevent recurrence and support healing, home care practices are recommended alongside medical treatment. Maintaining meticulous oral hygiene is important, including brushing teeth and gums twice daily with a soft toothbrush to avoid irritating lesions. If you wear dentures, remove them overnight, clean them thoroughly daily, and soak them in an appropriate cleansing solution to reduce yeast contamination.
Rinsing the mouth with water or a mild salt water solution after meals and after using a steroid inhaler helps remove residue. Managing underlying health conditions, such as controlling blood sugar levels if you have diabetes, is also a preventative measure. Avoiding the overuse of antiseptic mouthwashes helps maintain the natural balance of microorganisms, preventing future Candida overgrowth.