The prescription steroids in solution (a thin base, not creamy or oily) are the answer for rashes and itching on the scalp. I used fluocinonide solution daily, applied as carefully as possible to the scalp rather than the hair. The watery thin solution makes this much easier than it would be if you used a typical steroid cream. Good luck!
I did the same as Pooh. I also used coconut oil on my scalp and skin. It definitely helped. I know how you feel. My rash went from head to toe. Hang in there. Week 9 is soooo close to the end.
My dermatologist prescribed clobetesol solution for the scalp itching and rash and also oral hydroxyzine 50 mg. every 6 hours for itching and rash. They worked very well. Both are prescription medications.