Cat owners are not unfamiliar with the unpleasant sound of their cat regurgitating their lunch. Whether because of a hairball or the occasional upset stomach, cats tend to vomit every once in a while. However, these aren’t the only reasons your cat might be heaving and gagging. Vomiting in cats can be caused by a wide range of underlying problems—some more concerning than others.

Common causes of vomiting in cats

Cats might vomit for any number of reasons. Some are easy to detect, while others will require a professional diagnosis. Here are some of the most common:

1. Hairball: One of the reasons cats vomit is likely the most familiar to their owners: hairballs. Cats can’t digest the hair they inevitably swallow during their fastidious daily groomings. Although most hair passes through the digestive tract and exits in stool, some hair clumps get too big in the stomach and must be regurgitated up the esophagus. Hairballs typically look different from most vomit, since they’ll largely be composed of clumps of fur.
2. Ate too fast: When they get super hungry, some kitties just can’t control themselves and will eat as fast as they can! Unfortunately, with all that food hitting their empty stomach, your cat might begin to feel sick shortly after finishing their meal. When cats cough up intact food and fluids, it’s called regurgitation. Occasional regurgitation usually isn’t an issue, but it shouldn’t happen every time your cat eats.
3. Foreign object: Some cats are too curious for their own good and might eat non-food items that irritate their stomach. In these cases, the body forces the cat to vomit to protect them. This often happens when cats eat grass from the backyard.
4. Intestinal blockages: Foreign objects, hairballs or even tumors can lead to blockages in the colon. With food and waste unable to pass by these intestinal blockages, your cat might try to expel the contents of their stomach by vomiting. Other symptoms include constipation, vocalizing in the litter box and abdominal distention or pain. This condition can be extremely serious and requires immediate veterinary attention.
5. Poisoning: If your cat ingested a toxic substance, it’s likely that they’ll vomit repeatedly. Lots of things are toxic to cats, from household plants to human foods to cleaning chemicals. Toxic poisoning is extremely serious and will need to be treated by a vet.
6. Hunger: Sometimes, cats can get so hungry they literally make themselves sick. If your cat hasn’t eaten all day, bile can irritate the empty stomach and cause vomiting. If your cat is vomiting bile, you won’t see food—you’ll likely just see a clear or yellowish liquid accompanied by a foamy substance.
7. Food allergies: If your cat is allergic to an ingredient in their food, they may experience digestive symptoms as a result of food allergies. While some cats’ food allergies manifest as itchiness of the skin, others may experience chronic vomiting and diarrhea after eating. The vomiting may continue to occur until the food is changed.
8. Major diseases: Vomiting is also a general sign of illness for a large number of diseases, including liver disease, kidney disease, diabetes, hyperthyroidism and cancer. In these cases, vomiting will usually be accompanied by other symptoms of illness.

When should vomiting be a concern?

Because vomiting can occur alongside so many different health problems, it can be difficult for a pet parent to know when to be concerned. Vomiting is never “normal” for cats, but it does happen on occasion without any major consequences.

If your kitty vomits once or twice within one or two days but otherwise seems healthy and happy, it’s probably nothing to worry about. Keep an eye on them for any signs of illness and withhold food and water for a little while until they feel better.

If your cat has vomited multiple times, particularly over the course of multiple days, there’s probably something more serious going on. This is also the case if they vomit every single time they eat, they begin to vomit blood or they show other signs of illness. If you notice any of these issues, call your vet as soon as possible.

If your cat has begun to vomit, pay close attention to the situation. Did they just eat? Did they eat something they aren’t supposed to? How frequently is this happening? What color and texture is it?

Taking note of all of these things can help you and your vet figure out what’s wrong if the vomiting does continue. With your observations, along with some tests, your vet should be able to deduce the issue and help your cat get the treatment they need.