making a dermatological diagnosis requires an examination often by a dermatologist. a vague description is not sufficient information to make that important "what is it? " call nor is researching your skin condition on the internet. there are thousands of possibilities. as much as i would like to help it would not be possible to make a blind guess as to the nature of your itchy skin eruption.
i have a skin condition but it doesn't seem to meet any of the ones i've researched. what is it? immensely itchy. on my arms legs butt thighs and a few other places. i have raised skin that is skin coloured and in little patches. it itches immensely and comes and goes.