Allergy testing is expensive and also unreliable - so just keep that in mind. There can be a lot of false positives - and a good vet will even tell you that.
As for foods - I could find one thing common w/ RC and Hundchen and that was Flaxseed - which does bother some dogs bc they cannot convert it and it is grain related. But, pollen is also in season - so then I wonder if the itching is from that...? The Hundchen is a pretty darn good food.
I mean, you could go with something grain free and flax free - I'd recommend Natures Variety Instinct Duck and Turkey - bc they still their omegas from the Herring.
