Depression after vet trip?

I have 3 indoor cats, two of whom are older (about age 12) and litter-mates. Fudge, one of the older two, was a very adventurous boy for most of his life, and often would try to sneak outside the front door if someone holds it open too long and isn't paying attention. On Wednesday afternoon, my mom was carrying laundry in from the laundromat. That night, Fudge was nowhere to be seen, and when we couldn't find him in the morning, we figured he'd escaped. He'd never been outside that long, and we were unable to find him in the bushes. This was unusual, since he usually hid on our lot when he got out, but he had more time to wander in this instance. On Thursday evening we drove through our neighborhood and found a cat identical to him sitting about a block and a half away from our house. It had the same exact markings as Fudge, the same knot in his fur that we haven't had time to get out, and responded to his name. We put him in a carrier and kept him in the garage over night so that he could be checked out by the vet in the morning, as we did not want him to give any disease or fleas to the other two. He was in there all night, and we took him to the vet around noon on Friday. He seemed friendly and happy to get out of the carrier and be petted. The doctor thought he checked out alright, but we decided to keep him there over night just in case, so that any fleas that might be on his body would be killed before we took him home. We picked him up yesterday (Saturday) around noon, and as soon as we let him out of the carrier, he seemed not himself. He's a very friendly, happy type of cat, and he seems almost as if his spirit is broken. We figured he must be very tired and probably didn't sleep well at the vet's. In addition, he is older. I guess I'm just worried about the fact that he seems so depressed. Is it just that he's tired? Is there something I should do to cheer him up? I hate seeing the poor boy this way. Any suggestions would be wonderful.

It sounds like you are not sure if this really IS your cat. Could it possibly be a twin that actually belongs at the house where you found him (you said "in addition, he is older"), then perhaps it's just that since he was picked up by you, he had to spend a night in a carrier, then go to the vet, then spend a night at the vet before coming back to your house. 

If you have even the slightest suspicion that this might NOT be your cat, you might try checking with the people in the house where you picked him up to see if they have a cat, and if so, if he has gone missing.  If the answer is yes to both questions, then obviously get a description and if it fits, bring them the cat you have and see if it is in fact their cat.  It would be strange but not impossible, and that would explain the depression.  If he's a nice friendly cat, he would tolerate all that's happened but he would certainly be depressed to have been kidnapped from his original home.  This would be just one more example of why it's good to have your cats microchipped even if they ARE indoor only cats!

Thanks for the reply. I am sure it's him, it just worried me the way he was acting. We took him to the vets and he has pancreatitis, so he's being boarded at the vet's again. He's in a lot of pain, so I'm sure now that it's him, and this definitely explains why he hasn't been himself.

So sorry to hear that!  There are many threads on here about pancreatitis.  Scroll up to the search box, right under the brown bar at the top where it says Forums, and search pancreatitis if you want to read other peoples experience with it etc.  Let us know how he's doing.