Connie and Charlie, you may want to consider getting your vet to
prescribe what our previous vet (a ferret expert) swears by:
"Tresaderm".  Our vet said that it's not normally thought of for ear
mites (being usually for Otitus externa and other dermatoses), but he
found it to be the quickest and most effective of everything he ever
tried.
 
The instructions we were given was one drop in each ear daily, for 1
week.  Stop for a week.  Repeat for a week.
 
Worked for us very quickly.
 
Active ingredients: Thiabendazole, Neomycin Sulfate, Dexamethasone.
 
The manufacturer is MSDAgVET, a subsidiary of Merck Frosst, Canada.
 
Dr. Williams?  Comments?
 
[Posted in FML issue 0716]