here is a bunch of info i wrote on allergies scroll down to first post and work your way up
http://www.yorkietalk.com/forums/yor...ml#post3147954
unfortunately our derm said environmental allergies are going to be bad this year too
so if it is that and she is rubbing at her eyes then you definitely want to get her on something like zyrtech which has been working well with allergy dogs but i would strongly suggest working with a dermatologist as allergies start in dogs from 6 mos to 3 years and my girl started around 6 mos
so this could very well be this since this breed tends to have poor immune systems but the derm will rule out food allergy and demodex first