I ordered Provent a Mite online since none of my local stores have them. Right now, I'm using Mite Off (made by Zoo Med). The bottle says it's okay for use on the snake itself; just avoid the head. Active ingredient is Sodium Laurel Sulfate 0.1%
I also changed the entire substrate and lightly misted the substrate and everything inside the cage, except the water dish.

The instructions on the bottle say...
"-Spray evenly over entire body, legs, and tail. Make sure to spray skin folds, as this is where many mites will hide.
-Thoroughly spray entire enclosure including substrate, rock heaters, cage furniture, etc.
-If mites are observed on your reptile(s) after 48 hours from the initial treatment, they are most likely dead and can be rinsed from the animal with water.
-Reapply as necessary, but allow 3 days between treatments.
- For snakes, lizards, and land tortoises only. Do not use on amphibians or arachnids."

Thoughts? Anybody use Mite Off before?