What kind of food are you feeding her????? Most yorkies are allergic to CORN and WHEAT products that are in most commercial dog foods. Check the ingredients list on the food you are feeding her and if CORN or WHEAT is one of the ingredients, change her food. Any food on
this list with a protein level between 20-30% is an EXCELLENT quality food with no corn or wheat products. If changing her food doesn't correct the problem, you will need to get the vet to do an allergy test on her to see what exactly she is allergic to.