Usually cortezone cream works well...If you are experiencing it on he scalp, there are several shampoos that contain "tar" in them...Ie. T-gel. Have you gone to a dermatologist? After 17 years of suffering, I would assume you have. If not, go!!

I had psoriasis on my scalp for the longest time. At first I thought it wasn't anything, just a dry scalp, but then as the humidity got worst, that's when it got bad. I just went to walgreens and bought this shampoo, it was about $12. It took a couple of weeks for it to clear up, but now I have no problems.

Aveeno is a really good on the skin without the funny smell of tar. Also watch what you eat, take an allergy test to see if you are allgergic to anything that you usually consume that way you can lower the amounts. My brother has it and he tried drinking more water keeping hydrated because his skin dries out quickly. Talk to a dermatologist and maybe sit out in the sun like an hour everyday. Uv rays help out a bit. They have treatments for psoriasis excema in uv boxes. Just think of it as a way to get a tan. :p