The
vet said to not switch to advantage because I would lose the protection
from
heartworm and ear mites.

Advantage makes heartworm medcine not work?????

Noooo. Advantage doesn't have heartworm preventative. Also, revolution is a
topical and not an internal as is Advantage. Revolution protects against
everything (heartworm, ear mites, fleas and deer ticks among others) common to
the wonderous beasts (Cats & Dogs). Sad that I can't get hens in the city
without really "ticking" off the neighbors. LOLOL

Just my 2 cents.........
Christine