Can you get Revolution Heartworm product? Maybe order online? Best treatment for Sarcoptic Mange Mites. Apply once, then repeat in 4 weeks, then once every month as heartworm/mite preventative. You will need a pymethrin(sp) creme from the doctor for you... one time application.
https://www.revolution4dogs.com/default.aspx
He will need to be tested for Heartworm first.