Have they eaten anything they shouldn't? A more serious reason a cat might throw up is to get rid of toxins, or because it has food poisoning.Although some cats will decide to stop eating as a result of changing a cat's food, which is very scary since anorexia in a cat often leads to fatty liver disease, which is fatal.
![cat salute cat salute](https://www.telegraph.co.uk/content/dam/news/2016/08/12/85423869-cat-xlarge_trans_NvBQzQNjv4Bqv3hxuICTza90rxjOncu1SG5Y7rtmR8s0ln1ITFzpyNA.jpg)
Fortunately, in most cases, once the initial upset occurs, they will get better. It is for this reason that it is not advisable to switch cat foods if possible.
![cat salute cat salute](https://kenpope.com/Timmy%20salute%20now.jpg)
Did you switch their cat food? Another less harmful reason a cat may vomit is if you change cat foods for your pet.Once the grass is out of their system, the vomiting will cease. You will know that is all it is because they will vomit just blades of grass and saliva. If this is the case, it is not anything to worry about. Did they eat grass? One reason a cat might throw up is if they just ate grass.A fur-ball will usually be a dry matted wad of fur, similar to the color of the cat but a little darker.
![cat salute cat salute](https://i.pinimg.com/736x/75/eb/77/75eb775a99e15d273234d9129b808846--jeeps-salute.jpg)
Even if he does not have a severe illness, dehydration may result, although don't confuse a common hairball as throw up.