I like Minksheen shampoo, it has conditioners and mink oil in it, with cintronella to help keep fleas away. I also would use a leave in conditioner. Here is the link for Minksheen:
MinkSheen Pet Shampoo, 16 oz
But if she has mites maybe the vet would recommend a medicated shampoo for you so you might want to ask first. Good Luck to you and poor itchy Bella!