Don't rule out food allergies. My 7 year old Minnie has very dry flaky skin and is very allergic to certain dry cat food. She threw up 2-3 times a day for 2 years before we finally figured it out, (vet hadn't a clue, now have new vet).
It was the dry food we were feeding her. Believe it or not, we recently got a kitten and she started eating the kitten food. No vomiting and her skin is better! Have to watch the high protein in it I know, but she's better.
Don't give up. Try eliminating one type of food at a time if you feed dry and wet. You will slowly have to change the food by mixing it with another or she might not eat at all. Talk to your vet about best food for her age, and what to try. You might try one thing and it will get worse, but the ingredients will be what you want to avoid.
And NO table scraps! Read the labels on the treats too!
