I've had this many times. It's kinda like a flare up. I found that tea tree oil on the scalp overnight helps. Also a good tea tree shampoo. I personally use wen tea tree cleansing conditioners. It has helped with the itching and if you stick with it helps with re growth of hair. Everyone is different and you will have to try what works for you best

Yes I get that too. Along with the hair loss but 2% Minoxidil works for me it stops the itching and keeps,my hair from falling

I get the rash while I'm in the sun, or just heated. But this isn't a rash ... it's just an itchy scalp -and more hair is falling out.

I get it if I go into the sun - all over including scalp. I also get raised red bumps on my face, scalp and chest that itch like crazy, usually before and during a flare

Yes, I used minoxidil also but have to stop when my scalp flares and gets itchy burning pimples.