Suggest Treatment For Plaque Psoriasis And Joint Pains

I have pain in my joints starting with pain in my left knee about a month ago. Now I have been experiencing v more pain, in more joints and bones that have been previously injured. Sometimes severe. I also have been experiencing vertigo and headaches. I have mild plaque psoriasis, usually 3-4 dime size plaques at a time, but now it seems that I have many 15-20 on my body, showing my body is under stress. Any ideas?