I use Comfortis for both my dogs!! I LOVE IT!! I have been using it for almost a year now and no problems.. Mitzy has flea allergies and on frontline was still getting fleas (we live in south georgia so fleas are bad). Our vet had us put on Comfortis and no problems since!!
We also tried natural rememdies and I can tell you if you live in an area with alot of fleas and ticks they don't help much. I was doing brewers yeast tablets AND garlic and nothing helped. Its supposed to tast nasty to the fleas but honestly it did nothing to help my poor baby
