The vomiting is an active process that usually lasts a few minutes; the cat may retch, drool, look unwell and then vomit. A vomit that looks like poop may require medical treatment. There are 4 main reasons for cat vomit looking like poop.
Another reason cat vomit looks like poop is the liquid from your cat’s liver. The bile your cat vomits is commonly yellow; however, if your cat vomits brown bile, that can indicate that she has problems with her internal organs.
Cat vomit looks like poop if your cat’s stomach is dealing with gastroenteritis, which is swelling of the stomach and the intestines. The causes may be due to intestinal parasites, bacteria, medications, viruses, or food.