Cat Returning from the vet

Question
My cat, Lil One, went to the vet a couple times while I left my other cat at home. When I return from the vet, the cat that stayed at home hisses and growls for days to the cat that went to the vet. They were best of friends before the vet visit. This is the second time it has happened. The 1st time it took over a week before he befriended my cat again. Why is this happening????? I was thinking possibly it is the smell of vaccination????

Answer
Lawanna,

It's interesting that your cats do this.  My mom's cats do the same thing, and I've heard other peoples' cats that do it.  I actually read an article awhile ago that stated that no one really knows why cats act like this when one cat comes home from the vet.  Some vets believe that the cat that comes home from the vet just has so many smells on it (like other cats or dogs), and so the cat that was left at home thinks he's been around another cat.  It's unlikely the smell of vaccination--just all the other animal smells that are found at the vet.  

Unfortunately, there's not much you can do.  You just have to let them readjust.  You may want to get some Feliway and either plug it in 12 hrs or so before you take the other cat to the vet, or else buy the spray, and spray some around your home before you leave to take your other cat to the vet.  It might help calm the one left at home.  Or, you can get them on the same vet schedule, (ie, they go to the vet together for their routine visits) so they both come home smelling like other animals.  

No matter how you do it, it's always possible your cats will hiss and growl at each other when they come home from the vet.  You just need to let them work it out, and know that in a few days the smells will have gone away, and they will be back to their normal selves again.  But do try the Feliway--it may help.

Savannah