Why Is My Cat Throwing Up Undigested Food?

Cat Eating Out of a Bowl

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Vomiting is not normal in cats, and when your cat vomits undigested food, it can be a sign of a serious illness. Vomiting itself is what is considered to be a nonspecific symptom. It could be associated with an array of health concerns. Some of these can include things like hairballs, internal obstructions, pancreatitis, eating too quickly, constipation, indigestion, parasitic infections, poisoning, stress, depression, or even anxiety. But what could be causing your cat to vomit undigested food specifically?

What Is the Difference Between Vomiting and Regurgitation?

Vomiting is not always vomiting, sometimes it is actually regurgitation and knowing the difference can be helpful information for your veterinarian to help diagnose the cause. Regurgitation is often mistaken for vomiting, but unlike vomited food, regurgitated food has not yet been digested by stomach acids. 

Vomiting is when the contents of the stomach, including food, water and/or bile, are ejected. Vomiting is an active process typically accompanied by nausea, retching, and contraction of the abdominal muscles (heaving). The cat will often vocalize, drool, or begin retching prior to vomiting. 

Regurgitation, on the other hand, involves only the contents of the mouth or esophagus. Food and/or water or other ingested items do not make it to the stomach before they come back up, and there is no abdominal effort. Regurgitation is a passive process in which there is not vocalizing or retching, and the cat just lowers their head and food, or other materials fall out. Regurgitation often happens within 30 minutes to two hours after eating. 

Common Causes of your Cat Vomiting or Regurgitating

Your Cat Eating Too Fast

Some cats may eat too quickly and this can cause them to regurgitate undigested food. Feeding your cat out of a food puzzle toy can help to slow them down. Food puzzles are a great source of both play and enrichment for your cat. There are more and more manufactured food puzzles available on the market that stimulate both your cat's predatory and foraging instincts. The added benefit of food puzzles for a cat that chronically vomits their food, though, is that it slows down the chow time so that a cat can't eat too quickly and then get sick from it. If your cat routinely eats out of puzzle feeders and is still vomiting up their food, talk to your veterinarian. 

Food

Some cats may eat too fast as stated about or have a food allergy. If you cat is a habitual 'scarf and barf' cat or if they have intestinal sensitivities, that may be causing them vomit up partially digested or undigested food. If your vet has ruled out other medical issues and thinks that what your cat is vomiting up is actually food, they may want you to try a commercial, sensitive systems food with your cat. If your cat is still struggling with vomiting food on this special diet, they may then want to put your cat on a strict, hydrolyzed protein diet.

When it comes to food allergies, most cats are actually allergic to the protein versus any other nutrient source. A hydrolyzed diet is a food that has gone through a process where the protein is broken down into its individual amino acid components. This prevents your cat's immune system from identifying the food as containing an allergen and prevents your cat from having symptoms of an allergy flare up.

Hairballs 

Cats are naturally meticulously clean animals and groom themselves for a large part of their day. As your cat grooms themselves, tiny hook-like structures on their tongue catch loose and dead hair, which is then swallowed. The majority of the hair passes all the way through the digestive tract with no problems, but sometimes the hair stays in the stomach and forms a hairball. 

Hairballs can contribute or cause a cat to vomit up undigested food. Although, a cat vomiting a hairball occasionally can be normal and not a concern, it is important to note that hairballs should not be frequent, painful, or difficult for your cat to pass. To help prevent hairballs in your cat, there are over the counter dietary supplements, in either chew or gel forms. Adopting a regular brushing schedule and getting your cat comfortable with brushing can also help get rid of any loose fur in your cat's coat that they may otherwise ingest when grooming themselves.

Food and Dietary Changes 

When there is a change in your cats feeding schedule, if your cat misses a meal or eats later than normal, your cat may regurgitate undigested.

In addition, you may have switched your cat’s food too quickly. When changing your cat to a new diet, it is recommended to do it gradually over a one to two-week period gradually decreasing the amount of current cat food while increasing the amount of new cat food.

Your cat may eat too quickly, and this can cause regurgitation of undigested food. A cat vomiting due to eating too much is less likely but feeding your cat smaller and more frequent meals may help. You should also talk to your veterinarian about how much you feed to verify your cat is not being fed too much and is getting the nutrition they need. 

Gastritis  

If your cat is one to get into things they shouldn't, it is possible that they have irritated their stomach with something that they have eaten. When this happens, you may see vomiting undigested food in addition to vomiting blood and/or bile. Your cat may also be exhibiting a decrease in appetite, a depressed attitude, lethargy, or dehydration. Your vet will know just what to do if your cat is vomiting because of gastritis.

Some other causes can include 

  • Motility disorders
  • Esophageal irritation 
  • Parasites
  • Constipation 
  • An obstruction of foreign material in the intestinal tract

What Should I Do if My Cat Is Vomiting Undigested Food? 

Some cat owners may describe their cat as 'puke-y' but it should be noted that frequent vomiting is never normal for a cat. Vomiting more than once a week is definitely a sign of problem. If your cat is vomiting up undigested food, begin to feed with puzzle toys and/or feed them smaller amounts more frequently. If you continue to notice your cat is vomiting undigested several times and/or in conjunction with other symptoms such as lack of appetite, weight loss, lethargy, or diarrhea, you should make an appointment with your vet right away.

Your vet will want to start with a physical exam, checking your cat's vital signs and palpating your cat's abdomen. After a thorough examination, your vet may also want to run some tests, including blood work and X-rays. Blood work will check your cat's organ function, making sure that there are no signs of liver disease or kidney disease, as well as your cat's red blood cell and platelet levels. An X-ray study will check for any fluid in the abdomen that could potentially be blood and it may also show intestinal gas patterns that could be indicative of a blockage. 

Depending on what your doctor finds, your cat may require hospitalization for fluid therapy and supportive care, or they may just need outpatient treatments and oral medications to go home on. If your vet suspects your cat has an intestinal blockage your cat may require surgery to remove whatever the blockage is. 

Article Sources
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  1. Food Allergies. Cornell Feline Health Center

  2. Vomiting. Cornell Feline Health Center