Cat vomiting on food change usually takes 2-3 days to get used to. Cat food changes should follow the scientific 7-day food change method. The new cat food should be converted gradually, with the new food mixed in with the old food and the new food added in smaller and larger amounts. To change the food and vomit, stop feeding the new cat food, fast for half a day, feed more water, and feed some probiotics to regulate the gut.
