HELP! My cat continues to vomit.

Here is the story: Shelby was vomitting every 1/2 hour yesterday mourning so my wife and I took her to the emergency VetCare. The vet could not determine anything as of yet(waiting for the CBC results) so they administered some fluids to keep her hydrated.
Well, this mouring around 4:00am she started vomiting again. I suspect the shot they gave her has worn off and she has not eaten/drank anything since 11 last night. The local cat hospital does not open till 9am (2.5 hours) and my wife and I are very concerned. After a few hours of internet research, the only conclusion I can come up with is an inflammatory bowel disease "IBD"
Have any other cat owners had to deal with IBD? Please Help. Thank You.

BTW, Shelby is just under 5yearsold, indoor cat, and NO change in food/diet.
Everything was normal untill yesterday.:sick:

Another possibility is a blockage. Cats like to eat some strange things (elastic, Q-tips etc) and sometimes the item gets stuck.

Thanks Lucky Rescure.
After taking her to the vet yesterday, Shelby has a liver infection:sick: . So she is getting a steady serving of antibiotics and fluid. Her appetite is all but gone so we have to feed her through a saringe. If conditions dont get better, then we will have to but her up in the hospital under constant observation.

Good luck with Shelby,hopefully the antibiotics will do the trick,thank's for taking such good care of her:love:

Sorry to hear about Shelby.:sad: She`s lucky to have such caring parents.:thumbs up Let us know how she makes out.:fingerscr :fingerscr :pawprint: