flare up of scalp psoriasis, cannot seem get rid of plaques and itching

I have suffered on and off for 15 years, currently experiencing a very itchy flare up, have odd plaques all over body, a big patch on my knees and elbows . Are treating with dovonex, reduced scaling and itching on body but even with the gel having no luck with my head. I have quite long thick hair , am trying to part it to apply the gel but its just not lifting the scale! Its driving me mad and affecting my confidence.