Hi, I can help you with your question today.
I'm concerned that a cat of his age could have IBD (inflammatory bowel disease) or intestinal lymphoma, given the chronic vomiting.
I highly recommend getting an abdominal ultrasound done with a board certified internal medicine specialist.
They can recognize changes in the appearance of the intestines which could be consistent with either condition.
If ultrasound is not an option for any reason, you can ask your regular vet to prescribe an oral steroid, prednisolone.
Prednisolone can be helpful in the treatment of both IBD and lymphoma.
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