What are you feeding her, how much, how often, etc?

What kind of litter are you using? What have you done to
encourage her to use her box, if anything?

What has the vet said about her stomach sensitivity?

There are so many things you can try. She is way
underweight and that is dangerous to an older cat.
You need to find a food she loves that will also
firm up her stool, or to which you can add
things that will do it, among other things.

It could be many things (inflammatory bowel disease, lymphoma, etc).
Gail

With the readout from a full blood panel - which would show her various
liver & kidney levels, along w/ a myriad of other things, the vet should be
able to recommend a treatment regimen, to help her feel better than she does
presently.  (One of my cats had chronic liver disease, then chronic renal
failure for the last 5 years of her life.)

I'm also wondering about her thyroid function, since she's very thin -
hyperthyroid cats eat plenty, but get thin.  Of course, chronic renal
failure & liver disease can have that effect, too.

Regarding her kidneys, K/D is a good first step.  She may also need
sub-cutaneous (sub-Q) fluids once a week or more to keep her hydrated, esp.
since she has loose stools & is vomiting.  If fluids would benefit her, they
can be given at the vet's, or the vet can teach you how to do it at home -
easier on both you & the cat.  It's a quick procedure - approx. 5 minutes
start to finish - or less.

My cat who had a liver prob - which turned out to be a chronic hepatitis; I
took her to a vet internist for a diagnosis & recommended treatment - he
then contacted my own regular vet, who continued on w/ the treatment.  They
able to get her on a regimen which worked; slowly, but it worked, & 4 years
after she was diagnosed, her former off-the-chart liver values were once
again normal.

So, if you feel that your cat isn't progressing enough, you can ask your vet
for a referral to either a feline specialist, or IMO/IME, preferably an
internist vet who can most likely get a good handle on her probs & recommend
a treatment.  Even though she is 15.  The fact that her appetite is fine, is
good.

Good luck.

Cathy

--
"Staccato signals of constant information..."
("The Boy in the Bubble")  Paul Simon

I would think she might have a food allergy.  Also, have you had her checked
for Bartonella, and/or cardiac issues?  Often cardiac problems will cause
cats to vomit frequently.  -- M9

circa 7 May 2004 15:11:40 -0700, in rec.pets.cats.health+behav,
jks0614 (jks0614@comcast.net) said,

Has your vet checked her out for cancer and/or IBD?

Laura