Dear friend,
I do not think this is related to the food change. Your girl has stopped eating because she is not feeling well. A senior cat can have dental isssues, kidney, liver, pancreatic or thyroid dysfunction. She can aso become diabetic - have high or low blood pressure,Impacted hair or feces, etc.
This can become very serious because she can become dehydrated and develope liver failure from not eating and drinking.
First, check her mouth for any abscessed teeth, gigivitis or dental problems. Next you must get her fed and hydrated. Get unflavored pedialyte and canned cat food. Give her one dropper of pedialyte every ten minutes for two hours. Water down the canned cat food to a gruel and give her one dropper every 10 minutes for two hours after the pedialyte.
If she continues to vomit you will have to take her to a vet for subcutanious fluids so she does not dehydrate.
Please get back to me and let me know how she is responding. If you still have any questions please do not hesitate to ask. I will be happy to help in any way possible.
Very sincerely,
Terri
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