Key Facts Oral thrush, also known as oropharyngeal candidiasis, is a fungal infection caused by a yeast called Candida. While small amounts of Candida are usually harmless, an overgrowth can lead to symptoms. The condition can affect people of all ages, but it’s particularly common in newborns, the elderly, and individuals with weakened immune systems. The main symptoms are white patches on the tongue and inside of the cheeks. Oral thrush can usually be effectively treated with antifungal medications. What is Oral Thrush? Oral thrush is a condition where the fungus Candida albicans overgrows in the mouth and throat. Candida is normally present in the oral cavity, but under certain…