Well.. could be so many things for allergies to happen though. Any change to her food, her shampoo, etc? Cleaning supplies for home like laundry detergent, soap, shampoo, etc.. Do you wipe her down after every walk? Not just her paws but her whole body. Does she lick her paws?
Below is a link to a post by someone else with similar issue. Maybe you can get more info there? Someone said add little coconut oil in their food...
http://www.yorkietalk.com/forums/sic...y-so-much.html