I'm no cat expert, but when my cat was very ill, vomiting a few times a day, not eating, losing weight he was hospitalized and put on iv, he was actually in hospital for a week. They ran all kinds of tests and finally thought it was inflammed bowel disease he did start out with bladder crystals but got sick again afterwards. He has been on predizone every day ever since. That was about 3 or 4 years ago so I can't remember all the things they tried. But it was very scary.
Maybe u could ask your vet about inflammed bowel disease.
I sure hope he will be ok, poor little guy.
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~Tegan 9 year old yellow lab~
~Wilbur 9 year old LH cat~
~Mirabelle 18 mos dsh~
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