Suggest Treatment For Itching In The Body

I have an infestation of itch mites than never go away, because I can not see them, but feel the itching on various parts of my body and feet. It has been more than 3 years. The mites will stop temporaryly after the permethin, but come back in a week. Is there a Dr. in Arizona that can give me medications to rid myself of the mites?