So, about 5 or 6 months ago, I suddenly got this incredibly itchy rash over most of my body. It started as a patch on my back, like an irritation from fiberglass or rubbing on something. Eventually it was nearly everywhere, from my scalp to my legs. I had recently switched laundry detergents, so I thought it was an allergic reaction. I took a lot of benedryl and used hydrocortisone cream, but it didn't completely help. Eventually, it just went away after a couple of weeks.
Now, it's coming back. Same itch. Same rash. It's a red rash of many small slightly raised irregular spots (not bumps, pimples, or blisters). No other discoloration, fluid, crust, etc. Like before, it is concentrated (and most uncomfortable) on the upper pelvic area and waist, backs of the hands, and scalp. Some on the shins as well. It is most notably NOT on my feet, genitals, or back of my body at all.
No other symptoms. It just itches like hell, and if I scratch, it turns red and itches even more. The only thing different than before is I haven't changed anything. I'm not eating, wearing, or washing with anything new. I've ruled out most infectious diseases, fungi, and parasites that I have read about.
Anything sound familiar?