About 2 weeks ago I awoke with an itchy rash on one arm. (No pain whatsoever, throughout this even.) From pics available on the web, it looked most like atopic dermatitis. Next day there were patches on the other arm as well, and in the cleavage region, and itchiness had really increased. Did not use new detergent, lotion, perfume or soap, no new clothing, no new skin-to-skin contact, and since it's winter here in MN no exposure to any other external sources of itch. The next morning the rash was on my right thigh and calf. Next day, appeared on the left thigh and buttocks. For 6-7 days new body areas became covered in an intolerably itchy rash Over the counter antihistamine helped with the itch. The other thing that helped was scratching spots until I had a small amount of blood -- just a drop or two, and just two or three scratched spots per area (i.e., two or three small spots on my left thigh helped out the whole thigh.) Within a bit more than a week, rash had disappeared from all body except two areas: the area of cleavage and under the breasts. By that point rash was still there but no itching.
Fast forward another week or so. Now there is severe itch in exactly the same places as before, plus a few more areas where I hadn't had rash before. This time, there is no rash at all (except the remaining breast area rash that never cleared up the first time). The itching is as horrible as before and now scratching a few spots until they bleed has no effect, at least after the first few minutes when isolated, mild pain seems to have replaced the itching. Antihistamine helps, but not nearly as well as before.
The only body areas left completely free during entire process are my face and scalp, both hands, and both feet.
What in the world? What itchy kind of rash appears in new sections, day by day, for 6 or 7 days, then disappears, to reappear with no rash with an even stronger itch but now with no rash and all at once?