Good morning! It sounds like your cat is having a tough time adjusting to the new food. Are you gradually switching, or did you just change over all at once?
She was doing all the throwing up before I tried the food change. I am gradually changing by mixing some of her proplan into the new food
This morning she just threw up white foam, no food
It doesn't sound like the food change is the main problem, then. Cats who vomit chronically (more than once or twice a month) sometimes have a food intolerance (which is why you are switching foods is my guess). Sometimes the problem gets worse before it gets better. You can get some medications from your vet such as an antibiotic (metronidazole) to help with the bacteria shift which usually is the cause of the problem. At home, you can try giving a 1/4 tab famotidine (brand name pepcid) for upset stomach. Give this once a day. You may need to give steroids for a little while to get the problem under control.
For more information on dietary intolerances in cats you can read more at: peteducation.com Search for IBD cats and it will give you a great article.
Thank you very much Doctor, I will do that. Have a good day.
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