Several months ago I adopted a cat from the humane society - shortly after I got her - she stopped eating, so I took her to the humane society vet clinic. It turned out her bone marrow stopped producing red blood cells and she was Jaundice - and had to be put to sleep. The humane society said I must have adopted her that way - and apologized and let me pick out a second cat for free.
I picked out a cat that was 1 year and 6 months old, and just nuetered in early November. Since I have gotten him home he has been extremely playful and eats alot - but has also always had diarrhea! I took him to the vet for it, and she gave me a deworming treatment that I started giving him last week. In the last two days his appetite has really decreased and he has been much more lethargic than usual.
Since my first cat was so sick - and her symptoms were no appetite, I am quite worried. Any ideas?
The only other change has been that I got a christmas tree a few days ago also - he likes to drink water out of the base for it. I asked some of my friends that have cats - and they said their cats have been known to do that around christmas time also - and never got sick from it.
I'm worried that perhaps what ever my first cat had - my second cat has somehow caught?!
Since I'm relatively new to cat ownership - I'm never sure if I should be worried or not... Any help would be great!

Hi
I'm a vet tech, so I may be able to help you out, or at least give some advice on what MAY be going on. This is by no means any kind of diagnosis or treatment plan, but just my personal advice. Hope it helps.
The diarrhea your cat was having could be from stress and a new diet since bringing him home. A dewormer is always a good idea, and won't hurt if he doesn't actually have worms. I've heard of rare cases, though, that a cat can be so infested with intestinal worms that after given the dewormer, he can actually block up. A blockage is also a possibility if he's been around the Christmas tree. Cats love to eat tinsel, garland, etc off trees, and these can also block up the intestines.
Signs of blockage include lethargy, lack of appetite, vomiting, and constipation. For now, I would get a bland canned food from the vet - most vets carry Hill's A/D, which can be good for upset stomach. You can also try plain meat babyfoods. These don't have salts, etc that would worsen an upset stomach. Also, you might try adding some laxatone (or any hairball treatment) to aide in passing foreign bits in the intestine.
If he doesn't improve after 24-36 hours, get him to a vet for an exam. If a cat goes too long without eating, they can develop a serious liver problem. The vet may want to check a fecal sample, urine sample, and do some bloodwork to see if they can find anything wrong. Checking for Feline Leukemia and AIDS is always important, so I would recommend that no matter what.
I hope this helps. I don't want to scare you, but when a cat starts showing signs of being sick, it can be serious. Try the bland diet and laxatone for a day or two, then get him to a vet right away if he doesn't improve on that.
Good luck.

*feels like I am stalking tiger*

Definitely don't worry that your second cat could have "caught" the condition your first cat had, it is not a disease that can be passed or caught. I hope you will post and let us know how yer kitty kat is doing :)