I've never had a problem putting it on my dogs. That's what finally licked Leo's sarcoptic mange, after the ivermection didn't work. I do, however, have a couple of cats that get a localized reaction to it.
My vet has quit carrying the canine Revolution, though. They have had too many dogs on it come up positive for heartworm.
__________________ Lily Dale CA Speed Queen Leontine Von Washateria Ilka Of Pear Orchard Cemetery BN RE CA CGC Lucky Rat Dog CGC ~2000-2014~ Requiescat In Pace