Prickly itch post winter

[sacha]

I suffer autoimmune condition psoriasis and psoriasis arthritis. Mostly under control. Have couple of psoriasis patch in scalp all year around. There is one condition that bothers me and this the doctors have not been able to answer why it happens. Post winter as the weather warms I get this prickly itch under the skin. I can feel the prick ever part of the body that is about the sweat. What it could be, how to manage this. Thank you for reading and many things if you provide further inputs.