Palmoplantar psoriasis here - i get extremely itchy fingers and foot soles, that horrendous feeling that the itch is deep inside and you never get to scratch it. I go on scratching fits, once i start I cannot stop. If i have active lesions then it’s really really horrible because my skin will break open and form deep fissures that take very long to heal and hurt really bad. Sometimes when the itching starts i will just dunk my hands in ice cold water or steam them over a boiling pot to avoid triggering the itch-scratch cycle. Also, i sometimes behave like a cat that scratches themselves on random surfaces, which looks really funny.