Thrush is an infection of the mouth caused by the candida fungus, also known as yeast. Candida infection is not limited to the mouth; it can occur in other parts of the body as well, causing diaper rash in infants or vaginal yeast infections in women.
Thrush can affect anyone, though it occurs most often in babies and toddlers, older adults, and people with weakened immune systems.
What causes thrush?
Small amounts of the candida fungus are present in the mouth, digestive tract, and skin of most healthy people and are normally kept in check by other bacteria and microorganisms in the body. However, certain illnesses, stress, or medications can disturb the delicate balance, causing the fungus candida to grow out of control, causing thrush.
Medications that upset the balance of microorganisms in the mouth and may cause thrush include corticosteroids, antibiotics, and birth control pills. Illnesses or medical situations that make candida infection more likely to develop include uncontrolled diabetes, HIV infection, cancer, dry mouth, or pregnancy (caused by the hormonal changes that occur with pregnancy). People who smoke or wear dentures that don’t fit properly also are at increased risk for thrush. In addition, babies can pass the infection to their mothers during breast-feeding.