http://www.askthecatdoctor.com/CatVom... brings you this video illustrating the all too familiar sight of a cat heaving and vomiting. Cat Vomiting can be caused by many different things, from hairballs to toxins to diseases such as diabetes, kidney disease and hyperthyroidism. Unfortunately, in each case, the vomiting can look like that in the video so you really cannot know what is making your kitty vomit. That's why it's important to report all vomiting in cats to your veterinarian.