D.D.
I know you don't want to go to a dermatologist but it may very well be contact dermatitis. Ask him if he changed soap/shampoos etc. When it began. I have contact dermatitis and it is a pain in the butt if I touch anything that offends my skin. It causes problems with my hands and any thin skin on my body. I don't have any issues right now but I went to the dermatologist and was patch tested for offending chemicals...I found 2 that caused HUGE amount of damage.
My Dr is in Northbrook, IL...Dr Andrew Scheman. Let me know if you need any extra info. Best of luck to him. No psoriasis would last that long unless it is being "fed".
D.