Have you ever tried Revolution to prevent earmites? We started using it a couple of years ago for the indoor-outdoor boys. It's once a month, liquid on the back of the neck - prevents fleas, earmites, worms - and it works. The boys ears look as clean and pink as the day they were born.

You need a prescription in the US; but I found a place in Winnipeg, Manitoba, that is cheap and no prescription.