<human>: * My cat is 15-16 years old, and is generally healthy, I have not noticed any issues other than the fact that she's sensitive to touch but I assume that to be arthritis or some normal ailment for elderly cats. She doesn't tend to have stomach problems (doesn't throw up more often than any other cat), but today I woke up at 6 am to her vomiting and she is still frequently throwing up (it's now noon). I think it could very well be her food, as I just switched to a different brand the other day, however it is a brand I have fed her in the past with no problems. Has anyone else's cat had a similar problem? What should I do, if anything?

* Any advice on general senior cat care would be very much appreciated as well! I have been wondering if I should be taking her in for periodical check-ups at a geriatric vet/feeding her a special diet/doing anything different than I do with my younger cat?

* My older cat has a black coat, which has been turning brown recently. I have heard that this could be from some nutrient deficiency, and also that it is normal for aging cats.

* What is the best food to be feeding an indoor/outdoor cat and a senior cat? I am usually strapped for cash and opt for the less expensive foods, but I would be willing to spend a bit more if it means healthier kitties.

* And finally...what can I do about awful cat breath?!

Can you give me the gist of the text in a nutshell?
<bot>: Main point: what do I do about a tummy-sick kitty? (and several other cat-care questions)