If you notice a lot of dandruff, I would consider changing her food, whether feeding raw or a high quality grain-free kibble. The dandruff means her skin is dry and she'll likely scratch more, which won't help the skin or your husband's allergies. I am allergic to dogs and when I first got Scottie I suffered the whole itchy red watery eyes too, despite Yorkies being relatively hypo-allergenic. So it was very important to me that I got rid of his dandruff.
If you go with the grain-free kibble route, make sure you read the ingredients list. Prior to Acana and Orijen, Scottie also tried Fromm's Grain-Free kibble, which is known to be really good as well. They're really small bite sized pieces! Once you change the food, you may need to wait a month or so to notice changes. Just make sure you do the gradual transition if you do change kibbles. If you go with feeding raw, don't mix with kibble - they digest at different rates and could give your little one stomachaches.
Also consider giving her filtered water rather than tap water. That may help too. Yorkies are so sensitive
