I'm sorry you are suffering : ( 2 Of my staple things are borax and a bottle of kleen green enzyme spray.
Spray down good in the shower with the enzyme spray and leave on a few minutes while you make a watery borax/shampoo mixture. Then pour over your head, wash your hair and scruff your body with the run off.
This routine has helped me so much. And if I feel an itch any other time, I use the enzyme spray lightly on the area.
Usually when I get an itch I lay clear packing tape on the spot, then check under the scope and there's almost always a "sugar snake"(the long moving hairs) causing it... I ~really~ want to know what those are!