No offense to the Barkers but I refuse to spray anything on my snakes directly. I have seen animals react adversly to being sprayed with pyrethrins (probably not spelled right). I have no problem with spraying the cage down, and have had no problem ever ridding a new snake of mites with just spraying down the cage. Always works. (Although, I have to say, I have seen a collection of snakes that was riddled with mites and the darn things were immune to pest strips and provent-a-mite.)
I have also found that sprinkling the carpet with Sevon Dust works very well before vaccuming. If I do have a snake with mites, the whole carpet around the cage, gets sprinkled with the stuff. Prevents the little buggers from doing their walk-about around the house. (Nope, I'm not paranoid
)