My Creamsicle has allergies but we aren't sure what she's allergic to. I think she's allergic to treats and also Purina Cat Chow Indoor Formula. I had all my cats on regular Purina Cat Chow and switched to the indoor formula and that's when she started losing hair big time. She had bald spots on her head and her tail looked like a rat tail. So everyone is now eating regular cat chow and she doesn't get any treats. She's on Prednisolone for a little while until we're sure she's got all of the possible allergens out of her system. Good luck w/this. I know it isn't easy, especially if the allergy turns out to be environmental. Where in the world do you start?