My 8 year old cat is sick again

A few weeks ago, it all started was when we bought a new kitten from an animal shelter. She was not eating, and when she did she would throw it all up. We took her to the vet, and the vet said that there was something in her stomach. The cat was given antibiotics vomited clear mucus, and went back to normal.

Now, it's back again. She is still playful, but is dehydrated and not eating again. She coughed out, "k-k-k-k-k-k-k!" We're thinking it's because of the kitten's sneezing.

What exactly is it?
Asked Feb 16, 2015

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