Have you seen a doctor about it at all? I would recommend a dermatologist.

I had come down with an allergic reaction to cleaning solutions and the reaction was similar to psoriasis. I was given steroids and that cleared it up, but it was just a reaction.

I actually have a skin condition known as aquagenic keratoderma which is where the palms of my hands swell up when they get wet. It doesn't hurt usually, though my palms can swell to the point that they cause tension on the skin. It never goes over the folds of my hands though. I went to a dermatologist who prescribed me some ointment thing to put on every night; it has the key ingredient for deodorant in it so it's there just to dry out my palms. It works though, the swelling has gone down quite a bit since I started taking it! I may have to take it forever though...

That's part of the reason I say check with a dermatologist. I had seen my physician about it first and she didn't know, she just put me on 2 different strong steroids and gave me a steroid shot. I went to the dermatologist and she knew what to do and told me I may have it forever, which was the sad part.