[That he tries is all she asks. Besides, it's hard to get skeptics to really understand until a treatment is actually needed, most of the time.]

I would be happy to explain more at a later date. And one I can think of off-hand is the cure for Un. They're a rather common type that cause deafness by infesting one's ear and devouring all sound, but can be driven back out with application of a saline solution.

[Spoilers, the little buggers look like snails and slugs.]