Reasons Your Cat Is Throwing Up Clear Liquid or Foam

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Reasons Your Cat Is Throwing Up Clear Liquid or Foam

Have cat – have throw up. That is one of the less exciting parts of cat ownership.

Most cats will at some point throw up hairballs – or maybe even undigested food, but what happens when that vomit is clear or foamy and not a lump of hair?

Should you be concerned?

The answer is – sometimes.

If chronic vomiting is becoming an issue – your cat should see the vet.

Whether the vomit is clear or food based, chronic vomiting can be a sign of a more important medical issue.

If the vomit is not clear it can also mean other issues are present.

Vomit that is reddish or yellow in color can mean issues with the intestine or even liver disease.

Below are some reasons for this issue so you can understand when it is time to get a veterinarian involved.

Why Do Cats Throw Up Clear Liquid?

Clear liquid vomit from your cat is simply your cat bringing up what is commonly  known as “stomach or gastric juice” from the digestive tract.

It may sometimes seem kind of “slimy” which is the excess mucus that is coming from the esophagus.

The esophagus is the the tube that connects the mouth and the stomach and the vomit will travel that length to come up.

There are many causes of vomiting in cats which I will talk about in more detail below.

The most important thing you can do to help your cat is to pay attention to your cat’s behavior to notice if the vomit is increasing and to how your cat is acting.

It is also important to note any behavioral changes – if their normal demeanor changes, it can signal a bigger issue.

Related: How often should I take a cat to the vet?

Clear cat vomit is as clear as the name suggests, it may come out as a clear liquid or as a white foam.

You do not expect to see any solid food particle in this type of vomit.

The clear liquids always come from the cat’s digestive tract, which in many cases are stomach juices.

Some of the common reasons why a cat would emit the foam or clear liquid include:


Hairballs are a normal part of having a cat [1] and is the most common reason you may see clear liquid throw up.

They groom themselves often throughout the day and that can result in them swallowing loose and dead hair.

While it is common for your cat to poop out much of the hair – some may find itself stuck in the stomach which can result in vomiting.

But before that hairball comes out, a gastric liquid will come our first.

The best way to avoid your cat from having too many hairballs is to groom your cat more frequently.

You can also change their diet to one that includes a food that can help prevent hairballs.

If you notice your cat struggling to get a hairball up, then a visit to the veterinarian may be needed.


When a cat foams through its mouth due to the following reasons:

  • Eating too quickly or too much, to resolve this, introduce the cat to a slow feeder that will keep him from eating too fast and try and space his meals to avoid giving so much at once.
  • When the cat is hungry, too much acid in the stomach may rise and come through the mouth.
  • Lack of food in the stomach irritates because of the excess acid and thus causing vomiting.
  • Gastroenteritis and irritable bowel syndrome are some of the severe stomach conditions that may also produce white foamy liquid.
  • Nausea or loss of appetite due to cancer, diabetes, and kidney diseases can also force the cat to vomit foam or clear liquid.

Your veterinarian may offer the best prescriptions to cure these two stomach-related illnesses.

There are specific diets that the vet can suggest to manage the effects gastroenteritis and irritable bowel syndrome.

Poison Or Foreign Elements

Cats are inquisitive creatures which can sometimes get them in trouble.

Whether they accidentally ingest a poison or some kind of toxic plant, these types of things can lead to them ultimately throwing up some clear liquid.

If you notice ongoing issues with them throwing up and know they ingested something they should not have, then a veterinarian trip is recommended.

If they have ingested a foreign object that is blocking their intestinal tract, surgery may be required to remove it.

If they have poison in their system some kind of medical intervention may be needed to remove it entirely.

If a cat somehow ingests a toy – especially those string toys, it can also cause the intestine to be blocked which may required surgery to remove.

Any kind of foreign material can lead to the vomiting, so be sure to keep an eye on your kitty and keep them safe from any foreign bodies entering their systems.


I hate saying this, but yes – cat vomit that is clear or foamy can be a sign of cancer.

Although not the most common reason, still a reason that needs to be mentioned.

Catching cancer in pets early can make all the difference in how long you get to love on them, so if you are concerned about cancer then definitely get to your vet sooner than later.

Cancer symptoms can vary and are hard to easily see by us mere pet parents.

But if you notice the vomit is clear and your cat is showing other signs like a decreased appetite, weight loss, or diarrhea a trip to the vet should be a top priority.

Thyroid Issues

Clear vomit and foamy liquid can also indicate a thyroid gland issue, which more often tends to affect older cats but may be present in younger cats.

Alongside the vomiting, there may be symptoms such as weight loss accompanied by loss of hair, hyperactivity, and diarrhea.

Hyperthyroidism is the most common of the thyroid issues and causes an overactive thyroid.

Your cat may receive radioactive iodine therapy, anti-thyroid pills, or surgery.

Inflammatory Bowel Disease

When your cat’s gastrointestinal tract is frequently irritated it can be a condition called inflammatory bowel disease (IND).

This disease means the cat cannot properly digest and absorb food and it often occurs in older cats.

One of the signs of IBD is vomiting, so if your cat has frequent vomiting of clear liquid, this may be another reason and would call for a visit to the vet.

Depending on the cause of the IBD your vet will help you create a treatment plan to help them deal with the disease which may include a special cat food or medicinal options.

Eating Habits

Did you recently change your cat’s feeding schedule?

Did you change the type of foods you are feeding them? 

Doing either of these things without transitioning them slowly can result in unwanted vomit.

Cats can easily stress over things like new foods or treats and stress can be the culprit of them throwing up.

If you have recently adopted a new cat – they may have at one time felt the pains of hunger and now with food always available, they may eat too quickly and too much.

This is a defense mechanism to help them overcome that hunger.

Food puzzles are a great option to help them slow down while they eat.

Or you can try to feed smaller meals more frequently until they are confident they will never be hungry again.

When Is It Time To Call The Veterinarian?

If your cat is vomiting several times a week, it may be time to visit the vet.

If you notice the vomit is a clear liquid or foam like and they have thrown up like that more than a couple of times in a few days, then I highly recommend you get them to the vet to rule out any serious conditions.

If the vomit is a fur ball or has food in it, and only happens once or twice – your baby should be OK.

But again, if it is vomiting multiple times a week then a vet visit should be priority.

What Will The Veterinarian Look For?

Vomiting in cats that is excessive requires a veterinarian visit.

When you get there, the first thing they will do is a full physical exam which may include temperature checks, weight checks and external abdomen exams to check for blockages or hardening.

If they see issues of concern they may order additional tests like blood work to check organ function, an abdominal ultrasound or possibly an X-ray.

These tests will let the vet know if there is any kind of disease or foreign object that can be causing the excess cat vomit.

What Are Treatment Options?

Depending on the outcome of the diagnosis, treatment options may include an overnight stay to improve fluids or something simple like medicines.

Although anyone who has had to give a cat medicine, knows it is not simple!

If it is something more serious like a blockage, surgery may be required to remove the blockage.

If there is a diagnosis of some kind of disease, like cancer – then a health plan will be created with you and your veterinarian to get your kitty back on track to being healthy and happy.


[1] Sugarcane fibre may prevent hairball formation in cats – NCBI

Jill Caren CharityPaws

Jill Caren

Jill is an avid animal lover who spends her time helping animal rescues by photographing homeless pets and through her work on CharityPaws.

She is currently owned by Cleo, an American Pit Bull Terrier and Snoopy Cat. Her inspiration comes from her girls Ginger and Riley (RIP) – pit mix sisters who were loved family members for almost 15 years.

You can find her on LinkedIn and Instagram.

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