cat throwing up clear liquid and foam
Cat Health and Wellness

Why is My Cat Throwing Up Water and White Foam?

If your cat is throwing up white foam, it’s hard to know when to intervene.  You wouldn’t want to take your cat to the vet’s office unnecessarily, but you know there’s a chance they could be seriously ill. White, foamy vomit can be alarming because most cat owners don’t know what causes it.

Why do cats throw up white foam? Usually, it’s because the cat’s stomach or intestines have become inflamed.  Furballs, parasites, and food allergies are common causes of inflammation. Occasionally, foamy vomit is linked to other organs such as the pancreas (pancreatitis). So, unless the vomiting is a one-off, a vet’s visit is required.

If you want to prevent your cat from bringing up white fluid in the future, you should try to improve their gastrointestinal (GI) health (stomach and intestines). We’ll explain why most cases of foam vomiting occur, what to do, and how to support your cat’s GI health going forward.

Is It Normal for Cats to Throw Up?

If your cat is throwing up regularly, this is not considered ‘normal.’ However, most cats will vomit from time-to-time and throwing up is not necessarily a sign of illness.

Vomiting may sometimes be a behavioral issue, or it could be your cat’s way of expelling toxic substances. For example, cats sometimes throw up for the following reasons:

  • Running Off Too Quickly After a Meal – This can happen if the feeding area doesn’t feel safe for your cat. Kittens may also run off too quickly as they enjoy playing.
  • Eating Too Fast or Overeating – Overeating can sometimes be caused by an underlying illness, but it may also be caused by an irregular feeding schedule. Also, if multiple cats are sharing the same food bowl, they’ll try to gobble down the food faster.
  • Eating an Indigestible Substance – Cats may throw-up substances that their stomachs cannot process effectively. Cat eat grass, for example. Cats do not have the right enzymes to process grass, so they’ll usually regurgitate it. Some specialists believe cats eat grass on purpose to help dislodge fur, bones, or features from their stomach.

So, cats throw up for a bunch of reasons – not just because they are physically ill. Nevertheless, if it’s happening regularly, you should investigate what’s going on. 

Should I Be Concerned Tat My Cat is Vomiting?

Although occasional vomiting is not too concerning, you should seek immediate treatment for your cat in the following scenarios:

  • Your cat has been vomiting for more than 24 hours
  • Your cat is unable to eat or drink the day after vomiting (though it’s normal for cats to refuse food for up to 12 hours after vomiting)
  • Breathing difficulties
  • Your cat tries to vomit, but nothing comes out
  • Diarrhea and vomiting at the same time
  • Blood or green bile in the vomit
  • Your cat is throwing up white foamy liquid (especially if it has occurred more than three times in 24 hours and/or has lasted longer than 24 hours)

If your cat is throwing up white foamy liquid, they’ll need to be checked by a vet in most cases. A variety of diseases and lifestyle factors can cause white foamy vomit and these range in severity from mild to severe – as we’ll explore below.

Why Is My Cat Throwing Up White Liquid?

Your cat probably has an issue with their gastrointestinal (GI) tract. The GI tract consists of the mouth, teeth, tongue, pharynx, esophagus, stomach, small intestine, and large intestine. If any part of the GI tract becomes inflamed or infected, your cat may throw up a foamy, white liquid.  

If your cat is vomiting up white foam, your vet may diagnose ‘Gastritis’ or ‘Gastroenteritis.’ These broad-sweeping terms mean that a part of your cat’s GI tract has become inflamed or infected. To be more specific:

  • Gastritis – This refers to an inflammation or infection of the stomach.
  • Gastroenteritis – This refers to an inflammation or infection of the stomach and intestines.

GI problems can be acute (sudden and temporary), or they can be chronic (ongoing). This means some instances of vomiting can be cured quite quickly, whereas others may require long-term care and prevention.

What Causes Gastrointestinal Problems in Cats?

So, we know the GI tract is often to blame, but what actually happens in the GI tract to cause vomiting? The following factors could be responsible:

  • An Obstruction – Obstructions can occur in the stomach, esophagus, or intestines. They can be caused by medical or lifestyle factors – as we’ll explore below.
  • Furballs In the Stomach – Hairballs in the belly may cause stomach inflammation (gastritis), and they may even cause an obstruction in the GI tract.
  • Food Allergies or Intolerances – These can cause inflammation to the stomach lining.
  • Eating Toxic Substances
  • Colitis – Inflammation of the large intestine due to various causes. This usually leads to diarrhea as well as vomiting.
  • Intestinal Parasites – Various parasites can cause foamy vomit.
  • Bacterial infections
  • Cancer – Particularly tumors in and around the GI tract

Various GI conditions can cause vomiting and these range in severity from mild to severe.

cat throwing up saliva foam

Is My Cat Throwing Up White Mucus Due to An Obstruction?  

For your cat to stay healthy, food and water must pass through the GI tract efficiently. If there is an obstruction in the GI tract, your cat won’t be able to absorb vital nutrients from their food, and they may become dehydrated.

Obstructions can form in the stomach (gastric outflow obstructions) or the intestines. If your cat develops an obstruction in their intestines, it may be due to intussusception. According to AVCA, intussusception occurs when part of the intestine slides into the other – causing a blockage.

Here are the factors that cause these blockages:

  • Eating foreign bodies – this is the most common cause. Cats may swallow string, ribbon, bits of plastic or anything they can get their paws on. Cat hair can also cause a blockage, as we’ll explore below.
  • Tumor (cancerous or benign) – these can press on the GI tract and cause an obstruction
  • A hernia
  • Injury
  • Parasites

If your cat’s obstruction is in the stomach and they cannot digest food, they may throw up some hydrochloric acid in their vomit. This may have a mucus-like texture and will usually have a slight yellow tinge to it. Obstructions in the intestines can cause foamy vomit, but also diarrhea, abdominal swelling, and lethargy.

Is My Cat Vomiting White Foam Due to a Hairball?

Cats groom themselves daily using their tongue, and some of the hair inevitably enters the gastrointestinal tract. Most hair will pass through in your cat’s poop, but some may accumulate in the stomach. If too much hair collects in the stomach, this will lead to stomach inflammation. 

When your cat’s stomach is inflamed, they will try to ‘cough up’ their furball. Some furballs are difficult to bring up so your cat might vomit bile or watery liquid for several days before the hairball makes an appearance.

In a small number of cases, furballs can become lodged in the cat’s GI tract, causing an obstruction. You’ll probably need a vet’s help to dislodge the furball. This condition can become life-threatening if the obstruction is not removed.

Although we think it is “normal” for cats to vomit up furballs, there is limited evidence to suggest that feral cats have this problem. Coughing up furballs is probably not as “natural” as we think it is, so we should try to prevent this from happening wherever possible.

How to Prevent Hairballs and White Foamy Vomit

If furballs are becoming a problem, this suggests that your cat is swallowing too much fur when grooming and/or their GI tract is unable to process the hair effectively.

To prevent this from becoming an issue, follow these tips:

  • Regular Grooming – If you have a long-haired cat, it is important to groom your feline daily. Short haired cats may also benefit from a weekly comb.
  • Larger Kibbles – According to this report from Sage, feeding your cat larger kibbles might help to ‘clean’ the stomach. When the cats ate slightly larger kibbles, more hair exited their stomach and passed through feces. You can purchase larger sized kibble biscuits, though do introduce them slowly as your cat might need time to adjust.
  • Small Meals – According to Europe PMC, small, regular meals clean the GI tract more effectively than large, infrequent meals. So, if your cat is prone to furballs, try feeding them 3-4 small meals a day instead of 1 or 2 larger meals.
  • Gastric Lubricant – If your cat is having problems with furballs, your vet might prescribe a gastric lubricant. This will help keep the GI tract running smoothly.

If you follow this advice, the size and frequency of the furballs should reduce.

Food Allergies and Milky Vomit

Another common cause of vomiting is allergies. Food allergies are common in cats – especially pure breeds. If your cat does vomit due to an allergy, the vomit is often milky or foamy in texture. Again, this is because their stomach lining has become inflamed. In addition to white foam, you’ll probably also see undigested bits of food in their vomit.

If your cat has an allergic reaction, you’ll probably see some of the following symptoms, too:

  • Diarrhea
  • Intensive scratching (perhaps hair loss on the head or tail)
  • Weakness and lethargy
  • Cat acne

These symptoms can be caused by other things so it can be hard to diagnose food allergies. Indeed, there is no genuinely reliable diagnostic test for allergies, but there are ways you can manage them.

What Foods Are Cats Allergic To?

Some common cat allergies include:

  • Chicken
  • Fish
  • Eggs
  • Dairy (most cats are also lactose intolerant)
  • Grains (less common)

Cats tend to be allergic/intolerant to a specific protein rather than a grain, though some cats are occasionally affected by grains. If you think your cat might be allergic to something in their diet, there are a few things you can do to help:

  • Hydrolyzed Protein – Buy a cat food that is made with hydrolyzed protein. This means the protein has been broken down into small pieces – making it digestible for most cats.
  • Hypoallergenic Cat Food – There are specialist cat foods that are made with fewer ingredients, so they are less likely to stimulate an allergic reaction. The manufacturers switch the allergenic ingredients for ingredients that most cats can digest. It should be said that some cats may still react to these products.

It’s a good idea to notify your vet of any dietary changes so they can monitor your cat’s progress with you.

cat throwing up white mucus

Has My Cat Eaten Something Toxic?

If your cat has vomited white liquid several times in quick succession, there’s a chance they’ve eaten something toxic. Similarly, if they are gasping and heaving – but only a small amount of mucus is coming out – they might have ingested something harmful.

Many owners don’t realize how many potential ‘hazards’ there are in and around the home. Cats can usually sense what is edible and what is not, but that’s not always the case. The following household products can be toxic for cats:

  • Caffeine – Most of us tend to leave bits of coffee or tea at the bottom of our cups. If you leave these cups lying around and don’t provide your cat with fresh water, they may start drinking your leftovers.
  • Garlic and Onion – Most cats find it very hard to process these vegetables, so you shouldn’t allow them to eat your leftovers. The consumption of spice is toxic to cats.
  • Chocolate – Most people know that it is deadly for dogs, but chocolate can cause severe gastritis in cats, too.
  • Alcoholic Drinks – Again, cats may drink an alcoholic beverage if that’s the only fluid available.
  • Plants – Especially daffodils, foxgloves, and eucalyptus.

If your cat has ingested something toxic, you may see additional symptoms such as hyperactivity, disorientation, yowling, or diarrhea.

Which Parasites Cause Cats to Throw Up White Foam?

Lots of parasites can find their way into the GI tract – especially into the large and small intestine. According to Cornell, up to 45% of cats will experience ‘gastrointestinal parasitism’ during their lifetime. Parasites can cause diarrhea, lethargy, and vomiting.

The following parasites are particularly likely to cause vomiting:

  • Roundworms – Roundworms live in the intestines, and they can grow to become very large if not treated. A cat with roundworms will have a voracious appetite. They will most likely suffer from diarrhea and vomiting. If your cat has roundworms, you’ll probably be able to see evidence of them in their feces or the liquid they throw up.
  • Coccidia – This parasite is very common, and most cats will contact it during their lifetime. However, if kittens develop it, they may start throwing up very violently. A kitten with Coccidia can become dehydrated very quickly if they don’t receive treatment.
  • Fleas – Cats who have fleas are more likely to overgroom. The more they groom, the more fur will end up in their stomach. As such, it’s no surprise that cats with fleas often cough up more furballs.
  • Stomach Worms – These are quite rare in the US, but cats do occasionally catch them. They can cause persistent heaving/gagging and foamy vomit.

If parasites are left to fester, they’ll lead to weight loss, a poor coat, and mood changes. As such, it’s important to seek treatment as early as possible.

Other Reasons Your Cat is Throwing Up White Foam

Although foamy vomit is usually linked to problems in the GI tract, other parts of the body may play a role, too. The following conditions can cause your cat to throw up white liquid:

  • Pancreatitis (an inflamed pancreas)
  • Exocrine pancreatic insufficiency (the pancreas does not produce enough digestive enzymes)
  • Hepatic Insufficiency (liver disease)
  • Diabetes
  • Thyroid Disorders
  • Irritable Bowel Disorder – Some specialists believe this condition is mostly caused by mental distress rather than GI issues.

Indeed, if an old cat is throwing up white foam, it’s perhaps more likely that their condition is linked to one the chronic medical conditions mentioned above.  

Does My Cat Have Irritable Bowel Syndrome?

If your cat is vomiting white mucus, and they are having problems going to the toilet (constipation, bloating and/or diarrhea) your vet might diagnose Irritable Bowel Syndrome (IBS).

This condition occurs when the bowels become inflamed, but vets don’t always know why this occurs. IBS is a syndrome – so it’s a collection of symptoms that can be caused by various factors. The GI diseases mentioned in this article (allergies, parasites, etc.) could lead to a diagnosis of IBS in some cats – especially if these diseases do not respond very well to treatment.

However, it’s important to say that IBS is not always caused by gastrointestinal issues. Some scientists believe mental distress is one of the leading causes of IBS in cats. This makes sense because we know cats can become easily stressed if their environment is inadequate or they feel threatened in any way. So, if you want to prevent conditions such as IBS, try to create a calm and relaxing home for your cat.

Is My Cat Throwing Up White Liquid Due to Pancreatitis?

Although most cases of vomiting are linked to the GI tract, vomiting can occasionally be a sign of pancreatitis (inflammation of the pancreas). The pancreas is a small organ, but it plays a key role in digestive health.

The pancreas releases a liquid that helps the cat to digest fats, proteins, and carbohydrates. In some cases, the pancreas doesn’t release enough liquid (exocrine pancreatic insufficiency), or in some cases, it produces too much liquid (pancreatitis). If the pancreas produces too much of this liquid, it can seep back into the pancreas – causing inflammation.

Either way, issues with the pancreas will usually cause vomiting. They may vomit undigested food, mucus, and white liquid. Scientists aren’t exactly sure what causes pancreatitis. Nevertheless, there is research to suggest that ingesting insecticides, consuming too much fat in the diet, parasites or physical trauma may cause pancreatitis in cats.

Cats with pancreatitis often become lethargic and refuse food. They can become dehydrated very quickly so if left untreated, this condition can be life-threatening. As part of the treatment, your vet may prescribe enzymes to help your cat break down fats, proteins, and carbohydrates in the GI tract.

What to Do If Your Cat is Throwing up Foam and Not Eating

Although vomiting foam isn’t always a sign of severe illness, it can quickly lead to a severe secondary condition: dehydration. As such, there’s only so much ‘home care’ you can offer a sick cat.

According to the Blue Cross, you should care for a vomiting cat in the following way:

  1. If your cat throws up, remove all food for 12 hours but provide them with clean, fresh water.
  2. If they continue to vomit, they have diarrhea, or they are extremely lethargic, take your cat to vet. If not, proceed;
  3. After 12 hours have passed, offer them 1 spoonful of cat food.
  4. If they eat this, keep offering them a spoonful every 2 hours until they’ve eaten a normal portion. Return to normal feeding the next day.
  5. If your cat is unable to eat and drink anything 12 hours after they last vomited (or they’ve been vomiting on and off for more than 24 hours) it is important to see the vet. At this stage, electrolyte imbalance and dehydration become a serious concern.

A dehydrated cat may start panting, have sunken eyes, and their skin will start to ‘tent.’ You can check if your cat’s skin is tenting by gently pinching the skin at the back of their neck. If the skin does not ping back into place immediately, this suggests your cat is dehydrated.

Although dragging your cat to the vet can be stressful – and you’d probably want to avoid it where necessary – it’s best to err on the side of caution when it comes to vomiting.

How to Improve Your Cat’s Gastrointestinal Health

If your cat has a healthy GI tract, you may be able to ward off furballs and other digestive issues. The following tips will help support your cat’s digestive health:

  • Purchase a good-quality ‘complete’ cat food with digestible ingredients. If your cat has a suspected food allergy, your vet may recommend a hypoallergenic cat food with fewer ingredients.
  • If your cat eats kibbles, try offering them a slightly larger-sized kibble.
  • Provide plenty of water – this will help keep the GI tract running smoothly. It will also dissuade your cat for searching for (potentially toxic) fluids around the house. Many cats prefer running water so you could try offering a small water fountain instead of a bowl.
  • Try feeding your cat 3 or 4 small meals per day rather than 1-2 larger meals. This will promote good digestive health.
  • Don’t overfeed your cat as obesity will aggravate most of the GI diseases mentioned in this article.
  • Stick to a feeding routine. Try to feed your cat at roughly the same time every day to promote good GI health.
  • Keep food bowls, serving areas, and cat litter boxes clean to prevent the spread of infection. If you have more than one cat, provide them with their feeding bowl and litter box.
  • If you have a long-haired cat, groom them daily. Short-haired cats can benefit from regular grooming, too – especially if they tend to overgroom.
  • Overgrooming can be caused by fleas so make sure your cat is regularly checked/treated for fleas.
  • Stress is linked to IBS in cats, so try to provide a relaxing environment for your cat. Think carefully about the placement of their litter box, bed, and food bowls. Also, make sure they have a quiet space in the home they can escape to if necessary.

If you stick to these suggestions, your cat’s GI health should improve, and the frequency of vomiting should reduce.

Cats vomit up white foam for all sorts of different reasons, so it may not necessarily indicate a severe illness. If your cat throws up once, and you see no other symptoms, they’ve probably just ingested something that didn’t agree with them.

However, if your cat has been throwing up for more than 24 hours, they may have an obstruction in their GI tract. Regardless of what’s causing them to vomit, dehydration will set-in after 24 hours if your cat can’t take on new fluids. As such, it’s vital to see a vet at this point.

If your cat is throwing up foam once now and then, this indicates poor GI health. While it is probably not life-threatening, you may be able to improve your cat’s digestive health by following these tips. When it comes down to it, furballs are one of the leading causes of intermittent vomiting. As such, keeping your cat groomed and flea-free is the simplest thing you can do to improve their digestive health.