It's very odd for the vet to assume food allergies since they only account for about 10-15% of allergies in dogs - it's usually a total waste of time, just as you saw here. Meanwhile, your sweet kiddo is still itching. But hang in there.
She most likely has enviro allergies (pollens, grasses, dust, whatevs...) - which for many are year round (ie, dust!). If you suspect year round symptoms, then try Apoquel or Atopica or Cytopoint - these modulate targeted cells in the immune system to either reduce reactivity or block chain reaction that results in symptoms.
*** For this level of itching you're describing - honestly, I'd try Apoquel first - bc it acts faster during the ramp-up phase, and bc it's particularly effective for severe itch cases. Apoquel and Atopica can be *miracles* for allergy dogs - seen it here a million times! Or, discuss the injection Cytopoint - given every month for allergies - it's new and there are amazing reports for it!
Read this thread:
http://www.yorkietalk.com/forums/die...tart-here.html