D.S.
I have not personally had Thrush but I do know children who have had it. Yeast can be difficult to get rid of, but I though there was a mouth rinse that was needed to get rid of it. My mother had yeast and it took two doctors until she found the right doc to prescribe the right medication. A doctor actually biopsied my mother and had us scared to death thinking it was cancer. It was a yeast infection and was diagnosed by her dermatologist. Try a dermatologist and see if they can help you.