About four years ago, my then 12-year-old cat started to excessively groom himself, licking the fur off of his legs completely, until they were raw and sore. We tried flea treatments, steroids, and antibiotics, but nothing seemed to work. The vet suggested that it could be an allergy, but that determining what the allergy was could be challenging. I came home and did a little bit of research online, and learned that chicken was a common allergy in cats. I started my cat on a chicken-free limited ingredient diet, and he stopped licking! His legs quickly healed and he was back to his normal, cool kitty self.