Hi Kitty,
Yes I get psoriasis very easily, the skin variety, never had it in the joints, that sounds nasty.
As always, you should see a doctor about it, not listen to strangers on the internet.
That said, this is what I know about it.
I get it mostly on my legs and scalp.
Sunlight helps enormously. My legs almost completely clear up in the spring/summer when I start wearing shorts. My scalp is much worse in the winter when I'm wearing more hats.
Doctors will prescribe steroid creams for skin psoriasis which will clear it up but it'll come back if you don't get to the cause of it. I think you can get steroid injections for the arthritis variety but again, it'll come back.
Diet and poor gut health seems to be the main cause.
When I stop eating sugar, bread, pasta, tomatoes and potatoes, it goes away completely. When I ate a ketogenic diet I had no psoriasis at all, everything returned to normal.
I don't know how possible that sort of diet would be for you? It takes a lot of effort to get started and maintain it. Alternatively you could try cutting one thing out at a time and see if it has any effect. If you eat a lot of sugar, I'd recommend cutting that first.
But if you can't do that your doctor should be able to help with both skin and joint psoriasis.
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