Hi. My Daughter Is Four Years Old. She Has Had

Hi. My daughter is four years old. She has had 2 episodes of itchy tongue in the past 2 months. The first one lasted almost 2 weeks with some white spots on her tongue. This time the white spot is very small and its on the tip of her tongue. What can this be? When I first took her to see the ENT the white mark was gone and she said that although there was nothing visible on her tongue it sounds like it may have been a fungus. Today I have her Zyrtec and 2 hours later she stoped complaining. I don't know what to think. Any ideas ??