Fleas

[muttmechanic]

Do you see any fleas on him? If so then they are starting to notice a resistance to the active ingredient in frontline in some areas. I've had bad luck with the topical drugs so I've stopped using them completely. I was using a topical drug called vectra which you can only get at a vet and they wouldnt die even with that. So now I switched to the oral medications because there is no resistance that we have seen and there is less of a chance of user error. The only bad thing is that there aren't any oral medications that repel ticks.

If there isn't any fleas he may have a flea allergy and thats a whole different ballgame. Does he bite right above the base of his tail or chew at his front paws?