Hey!

Wow what an interesting reaction from the chemist!  I found when I had chronic dandruff (not at all the same I know) I couldn't find ANY skin stuff or hair product that would take the itching away, it was awful.
Then I found out that it can be caused by a vitamin D deficiency, and was advised by a friend to take vit D and evening primrose oil and I must say it's worked like magic!
Best advice I could ever give is to see if psoriasis is linked to any dietary deficiency, treat the cause not the symptoms!
Chinese herbal medicine can be really good for this btw ;)

Hope it helps :D
Kxx