"B" wrote

My cat is 16 yrs. old and for the past several months constantly
throws up. The vet did some blood work and his sugar was a little
high, which she attributed to the stress of the visit. His kidney
function is slowing down a bit and now she wants to take a urine
sample. She has changed his food to a type that can only be bought at
the office and is a gastroenteric formula. The food is not cheap, $34
for a case of canned and $28 for a 6# bag of dry food. I don't know
what to do for him; there are times that he doesn't seem to know where
he is or who I am. Is some of this just part of the "aging process"?

It can be several things but the 'don't know who he is or you who are' sends
a signal of kidney problems to me.

Kidney problems are far more common in Cats fed mostly dry food over years
of time. It doesnt matter that many of the web sites about this are wacky
'new age', it's a fact shown by stats but even those fed always wet, can
develop problems by age 16.

The only answer having dealt with this many times (I rescue elderly cats) is
to get more water into them then have a vet who actually knows geriatric
cats and how to read bloodwork. Most of the cats I have rescued have been
14-18 and fed crap like 'purina' until suddenly they 'developed problems the
owner could not deal with'. Basic alzheimers sort of thing.

At this point, I dump a vet who first takes me to the KD dry (or wet) stuff.
My experience is that they know far less than I do (and i am always into
follow vet advice normally but this is the exception if they do that).

Commmon sense, kidney problems in cats are usually related to not drinking
enough. Over years, this can make it worse and damage the kidneys. Cats
don't really like 'water' that much but an effective way to get them to
drink is by adding a bowl of salt-free broth (2-3 TB) about 3 times a day if
possible. Feeding wet food also helps a good bit.

I agree with one of the posters, that once you learn to read *labels* much
of the 'Fancy Feast' is workable. About 40% of the versions are grainfree.

Please do NOT take to hairball remedy laxitives. Sure, cats hurl hairballs
at times, but that is a laxitive which makes dehydration worse if your kitty
has kidney issues.