Cats will vomit within a week of changing food and will basically recover on their own in 2-3 days. When the owner changes the cat's food, he cannot replace all the food. He should use the old cat food with the new cat food and replace it gradually. Since the brands of cat food are different and the nutritional components are also different, when changing the cat food, we should try to keep the cat's food for as long as possible. Food transition time, reducing the risk of vomiting in cats.