Hi and WELCOME to YT
...glad you found us.
I feed pre-made raw...either Primal or Nature's Variety and I love it...been feeding it for about 6 yrs now. If you prefer kibble, I'd recommend Natures Logic..you may want to read about it as it's a bit different from other kibbles.
To me, it very much sounds like your kiddo has allergies. Food allergies, just fyi, are very very rare...more than likely it's enviro like pollens, dust, mites etcetera. Read this thread about allergies for sure:
http://www.yorkietalk.com/forums/die...tart-here.html
I have 2 yorkies w/ allergies and, btw, terriers are notorious for allergies. My Marcel is on Atopica and it was a miracle for him. My Wylie does get recurrent pyoderma (ie, staph intermedius in dogs)...and this is common for many allergy dogs, unforch. We treat w/ Simplicef x 30 days each time.
The very best thing you could do asap is get thee to a Vet Dermatologist! You can either continue to waste tons of $$ at a vet generalist like I did in the beginning...or...just pay for seeing the derm and get squared away right off the bat...as they will get you on track! Find a derm here:
acvd.org | Home | Veterinarians with specialized training in skin, ears, and allergy
I really feel for you bc allergies are such a pain to treat! And yup, Benadryl is usually a colossal waste of time, lol! You could try Zyrtec and Claritin, but often times you really do need the more potent Rx meds for these kiddos.
Btw, has her thyroid been checked? It should be, just in case. She hasn't had any fur loss or other weird seemingly-unrelated symptoms, has she?