(HealthDay News) -- Thrush is a yeast infection that forms in the mouth and on the tongue.

The U.S. National Library of Medicine says the following factors can increase your risk of developing thrush:

  • Using steroid medicines.
  • Having HIV/AIDS.
  • Undergoing chemotherapy for cancer.
  • Taking medications that suppress your immune system.
  • Having a weakened immune system, which often occurs among infants and the elderly.
  • Being in poor health.