How Can Scalp Psoriasis Be Treated?

I have fought what I had been told was scalp psoriasis for 25 yrs and it s getting to the point I can hardly tolerate the discomfort anymore. My dermatologist has been treating me with med s such as methotrexate, Enbrel, (and two other drugs that the name escapes me at the moment) for the past year and nothing helps. I have intense itching, scaling, heavy flaking, and it keeps spreading, etc. I use Derma-Smooth for relief about 3 x s a week.......I have little next to no relief. I am now taking plaquenil 20 mg 1 x daily, have been on for two weeks. Today I have broken out with a rash on my upper chest, between breasts, back of neck and the scalp itch is almost unbearable. Dr wants me to try for 6 more weeks, I cannot do that. Am thinking of turning to my primary doctor. Any other suggestions. Thank you.