Technically vomiting, colloquially known as puking, is described as the active evacuation of stomach contents.
It may be caused by disorders of the stomach but it can also be a clinical sign that can occur with many diseases or problems. It depends on the cause.
The characteristic hacking sound of a cat puking is familiar to all cat owners! Cats vomit occasionally from hairballs or mild stomach upset, but in some instances, vomiting may signal a serious medical problem. Treatment for vomiting will depend on the cause.
It used to be thought that some cats were just pukers, but chronic vomiting is a sign of an underlying problem. It’s normal for cats to puke up an occasional hairball, but vomiting that’s not hairball related is a sign of a medical problem.
If your cat vomits multiple times in a day or if you notice an increase in the frequency of vomiting, it’s best to discuss the problem with a veterinarian.
Cat owners are familiar with hairballs, which are the result of the cat's ingesting large quantities of hair during normal grooming, but puke that includes blood, bile, mucus or partially digested food indicates a serious problem.
By the way, there is a difference between vomiting and regurgitation.
Vomiting often lasts several minutes and the cat may look sick, drool, retch, display abdominal heaving, and finally vomit. Regurgitation happens quickly and often without warning. The cat is fine one minute, then suddenly pukes without retching or heaving.
The color of a cat’s vomit can vary depending on what the cat has eaten and that includes any non-food items, any dyes used in the food and a number of other factors. In any case, color is not a reliable way to diagnose the cause of the cat’s vomiting.
Here are a few of the most common reasons why cats vomit:
Hairballs
Cats have rough tongues and when they lick themselves, they pull fur out of their coats which is then swallowed. Large volumes of hair can accumulate in the stomach and are not digested, leading the cat to vomit a hairball. Usually this is not serious, but hacking up a hairball frequently can be an early sign of a gastrointestinal problem.
Gastroenteritis
e.g. an upset stomach, which can occur as a result of dietary indiscretion, toxins, or medication side effects, among other things. Some cases of gastroenteritis are mild and will resolve on their own, but others can be more serious.
Foreign Bodies or Obstructions
Cats have been known to eat things such as a toy, pieces of string, a hair tie or other foreign objects and doing so may cause blockage and damage to the GI tract that can lead to vomiting. This cause of vomiting is serious and requires immediate veterinary attention.
Food Allergies and Inflammatory Bowel Disease
Allergies are uncommon in cats, but they can lead to vomiting due to the inflammation of the digestive tract and some cats may also experience chronic diarrhea as a result of these conditions.
Illnesses
Chronic illnesses such as kidney disease, pancreatitis, and hyperthyroidism can all cause chronic vomiting.
Parasites
This cause of vomiting is more common in kittens, but can occur in cats of any age. Occasionally, live worms can be seen in the vomit.
Cancer
Cancers of the digestive tract are fairly common in cats and can cause vomiting. Cancers in other areas can also cause feelings of nausea, discomfort, and malaise which can also lead to vomiting.
It’s normal for your cat to have the occasional hairball, but any change in the frequency, volume, or consistency of vomiting is a cause for concern.
Also, vomiting is a cause for concern if it is accompanied by other symptoms such as:
Loss of appetite
Lethargy
Fever
Diarrhea
Changes in litter box habits
Other changes in health and behavior