Vomiting in cats, when to worry?

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Many times we believe, even though it’s wrong, that it is normal for cats to vomit frequently. However, the hairballs can be dangerous not because they can cause discomfort or digestive problems to cats, which in some cases may be related, but because they hide a multitude of problems and diseases of different natures.


Table of Contents
The mystery of the hairballs (trichobezoars)(#anchorname1)
Is it the hair that causes the vomiting?(#anchorname2)
My cat tries to expel the hair but she can't?(#anchorname3)
When we shouldn't worry about vomiting(#anchorname4)
What is the cause of my cat vomiting?(#anchorname5)
Final considerations(#anchorname6)

Vomiting in cats because of hairballs (trichobezoars)

Where do the hairballs come from? Cats spend several hours a day to keep their coat in the best condition. This, together with their rough tongue, makes the ingestion of hair something regular.

As the gastrointestinal tract of felines is adapted to ingest the hair, it is normal for it to be eliminated in the stool without a problem. However, if your cat is frequently vomiting and in the vomit there's just hair it can be so due to two causes:

  • 1. The cat swallows more hair than normal: This tend to happen to cats that groom themselves more than usual because of reasons like behavior problems, stress, pain, itching, allergies, etc.

  • 2. The cat does not expel the hair she eats: It happens to cats that suffer from various digestive diseases that affect the intestinal motility. The bowel doesn't function as it should and therefore the hair accumulates.

Cat diet can prevent hairballs and vomiting?




Nowadays a good diet can prevent the formation of hairballs. Fiber helps the animal to eliminate the hair she eats. Malt is also recommended, since it works as a mild laxative that, administered several times a week, helps to eliminate the possible accumulated hair.

Is it the hair that causes the vomiting?

First of all we should ask ourselves a number of things:

  • When your cat vomits… does she always (or almost always) vomit hair? If she doesn’t vomit hair… why do you think the problem is the hair?
  • How often does she vomit? If she does so weekly or once every few weeks it is normal and has nothing to do about it.
  • Are there other associated symptoms? If there are other symptoms (weight loss, anorexia, diarrhea…), the hair has little to do with the possible problem.
  • If you have two cats… do both of them vomit or only one of them? If it was because of the hair both would be vomiting as both have hair, isn't it? Note: If they vomit, both of them, it’s no longer only one problem, but two!!

An example: If my cat of 10 years vomits her meal (or drink) 1 time per week without hair, most of the times, and seems to have been able to lose some weight, then the hair is not the cause, my cat has a problem and vomiting is clearly a symptom of an illness.

Perhaps only in cats with long hair with a very sporadic frequency of vomiting (every few months) we may think of involving hair at the origin of a problem, but even this theory is currently challenged in veterinary medicine.

It can also occur that the cat has a voracious or increased appetite (polyphagia) for different reasons, in these cases it is more of regurgitation than vomiting. The cat food exits without being digested in a passive way (without forcing). It may be a sign of disease such as diabetes. It is also related in some cases with stress/anxiety and competitiveness among cats during meal time. In these situations it is advisable to give your cat small amounts of food many times a day. There are interactive feeders available in the market.

My cat tries to expel the hair but she can't

Sometimes when cats cough we get the impression that they wanted to expel a ball of hair and that "it got stuck". It is a good idea to come to the clinic to investigate the problem of the coughs, deal with the correct diagnosis and, in this way, treat your cat properly. Sometimes those are young cats who develop feline asthma. The diagnose is necessary to treat and prevent the animal passing her whole life with that problem, and go from bad to worse.

When we shouldn't worry about vomiting in

  • My cat is vomiting frequently, more than 2 vomits approximately once every month.
  • The frequency of vomiting has been increased.
  • If she vomits several times in the same day or in successive days.
  • The cat has more than 7 years and has begun to vomit for some time now.
  • The animal has other possible symptoms of illness: apathy, loss of appetite and/or weight loss, diarrhea, urinates/drinks more, etc.
  • If you have given malt to your cat thinking that it could be hair balls but she keeps vomiting.

In all these cases vomiting has nothing to do with hair. Our recommendation is to go visit the vet clinic as soon as possible.



What is the cause of my cat’s vomiting?

There is a multitude of diseases that can cause intermittent or chronic vomiting in cats, many of them can be detected on time in routine check-ups.

1. Digestive causes:

Infections that cause vomiting: There are a number of infections that affect the intestine and can have vomiting as symptoms: viruses, bacteria, parasites… In these cases the cat's feces is often mushy or with little consistency. It is common in addition that the feces smell especially bad.

  • Food hypersensitivity/Food allergies: In these cases the vomiting is related to one or more ingredients in a diet. It is recommended to make an exclusion diet with a hypoallergenic feed of hydrolyzed or novel protein during 2 months in a strict way, although most of the times the effect should be seen before.

  • Inflammatory Bowel Disease (IBD): This is a severe inflammation of the intestine, of unknown origin, in which many factors can intervene. The possibility of this disease is proven by using ultrasound to observe the thickening of the intestinal layers, and the definitive diagnosis is determined through biopsy.

  • Intestinal Lymphoma: It is the most common tumor in cats. This is a tumor that affects the lymph tissue, which is very present in the intestine. There are mainly two types: large cells lymphoma (more aggressive and with a worse prognosis) and small cells lymphoma (less aggressive and better prognosis). Luckily the small cells lymphoma is much more frequent than the first one and a cat with a good early diagnosis can enjoy an excellent quality of life for years.

  • Pancreatitis: The inflammation of the pancreas is a painful process in which there may be intermittent vomiting. The diagnosis is relatively complex, it’s based on blood tests, ultrasound, and finally biopsies to be able to reach a final diagnosis.

  • Cholangitis/Colangiohepatitis: It’s the inflammation of the bile ducts of the animal, sometimes affecting the liver as well. Often there is an associated infectious component that needs to be determined. The diagnosis is based on blood tests, ultrasound, cultivation of bile and ultimately biopsy for definitive diagnosis.

For cats, in particular because of their anatomy at digestive level, they may present more than one of these diseases at the same time (IBD, pancreatitis, cholangitis / colangiohepatitis). When the three organs are affected (intestine, pancreas and liver) it is called "triaditis".

2. Not digestive causes:

  • Chronic kidney disease: It is the most common disease in cats. 1 out of every 3 cats age 10, and 1 of every 12 cats age 15 and over suffer from it. When this silent disease progresses, the kidney cannot eliminate through the urine the toxic waste products such as urea. This causes gastric irritation and nausea in the cat, which ends up vomiting, at first intermittently, then continuously. It is diagnosed by blood tests and once detected it is confirmed by the examination of the urine and ultrasound, since there are diverse causes that may produce this condition.

  • Hyperthyroidism: This is a hormonal disorder. Very common in cats age 7 or more. It produces an excess of thyroid hormones that makes the cat vomit among other symptoms, such as weight loss with a good appetite. It is diagnosed by blood tests among other possible tests.

  • Diabetes: It is another common disease in cats after a certain age. There is a problem with the insulin that regulates the level of glucose in the blood, and one of the symptoms may be intermittent vomiting accompanied by others such as increased appetite, drinking and urinating more than usual, etc. It is diagnosed by blood and urine tests.

If the act of the vomiting in cats itself is acute i.e. your cat had never vomited and has begun vomiting a lot in the same day or for successive days, we should add other possible causes for this acute vomiting: ingestion of foreign bodies (strings…), poisoning (plants…), etc. In these cases, as logic dictates, veterinary care becomes more urgent.

Final considerations for vomiting in cats

  • If your cat vomits regularly or intermittently it is very likely that it’s not related to the hairballs.

  • It’s also important to remember that, given cat’s ability to hide the symptoms, it’s of vital importance to perform an annual comprehensive checkup adapted to the age of your cat.

Joaquín Albaladejo Velasco, graduate in Veterinary Medicine by the UMU and specialist in feline medicine. Works at the Veterinary Clinic of Ronda Sur, in Murcia.