Hello I Developed A Rash On My Chest A Little

Hello
I developed a rash on my chest a little on my back kind of pink, my primary doctor showed me photos of some rashes showed me the one that was mine, He said it would go away by itself, he had seen some cases of it does not know hat causes it.
He called it pityriasis. a month ago it was still there I went to a dermatologist and she said it was not Pityriasis and prescribed TRIAMCINOLONE ACETONIDE & MUPIROCIN...I has worked on my chest well , but now I have a rash on my scalp, with scabs and avery dry scabs also itches sometimes & I get headaches..I will go back to her to get some help it is awfull.