Cat is sick

Question
I took my one year old cat to the vet because she was sleeping alot, not eating and vominting.  They said it was from the new food i had been giving her for the last couple weeks so they gave me different stuff.  It's been three days and she doesnt seem to be getting much better and still isn't eating much. Does it usually take them long to recover from something like that or could there be something else wrong with her?

Answer
Most cats will vomit from a diet change that isn't done slowly, but a healthy cat will stop vomiting after 24 hours or so and shouldn't be lethargic at all.

Did your vet do a thorough exam on her? Has she been tested for leukemia? She could have gastritis which can be very serious and requires more than a change in food. The first change could certainly have started gastritis. She could even have pancreatitis from this and that is VERY serious. This is when the pancreas becomes inflamed and tries to digest itself. It is very painful and will make the cat very ill. She would be lethargic from this for sure.

I would call your vet tomorrow if she is the same and ask them for another exam and some medications for gastritis. Don't wait too long, as these conditions can go from bad to worse very quickly.