Have you tried narrow band UVB treatments? I have ezcema, and the light treatments really worked for me, I know a lot of psoriasis patients had good results as well. It's basically like a tanning bed but upright and the lights are targeted for a specific wavelength (i.e. ok for skin, you're not tanning). I went to the extent of buying a unit for in home treatments. Been using it for years, typically 3 times a week X 2-3 minutes per treatment. I continue to use topical treatments for my hands, but only when really needed.