What Causes Itchy, Burning Rash On Forehead Spreading To Face, Neck And Chest?

my 21 year old daughter has developed a very itchy, burning, flesh colored rash that started on her forehead and has spread in the past few days to her face neck and chest. She does not have any fever or sore throat and the rash is not red. The only other symptoms she has is that she feels very tired.