Firstly, you need to ascertain IF your cat is being sick. Cats are avid groomers and so it is not uncommon for them to regurgitate up a hairball. This isn’t vomiting. Vomiting is usually accompanied by symptoms of nausea such as lip smacking, hypersalivation and most importantly abdominal effort or a vomiting heave. If there is no abdominal heave and the food or hair comes up in the shape of a sausage (the shape of the oesophagus) this is regurgitation which has different causes, diagnostic route, and prognosis. Your cat may have a reduced appetite or not be interested in food at all if he/she is feeling nauseous and being sick. 

OK – so your cat IS being sick – What are the possible causes?

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There are many reasons why your cat could be being sick, and keeps being sick, some are detailed below: 

Food intolerance/ Allergy / Change in diet 

Changes in diet, particularly when the diet is changed suddenly can cause your cat’s gastric system to react and lead to vomiting or diarrhoea or both. When changing diet, your pet’s healthy gut bacteria must react and adapt. So if not given time to adjust, may not be efficient at absorbing the food’s nutrients and so your pet gets sick. 

Usually, this type of sickness resolves within a week or so when the gut bacteria have “caught up”. But what if it doesn’t?

It may be that your cat has an allergy or intolerance to the ingredients in the new food. Your vet may suggest a “food trial” which involves using a prescription diet or a diet with a novel protein and carbohydrate to help settle your pet’s tummy. Intolerances and allergies are relatively common in cats; with 30-50% of them responding to a prescription diet and needing no further intervention (compared to 10% in dogs). 

Parasites / Fungus / bacteria 

Most cats will come across “bugs” in their lifetime whether it through their lifestyle of being an outdoor cat and hunting or through their diet in the home. That is why vets recommend regular routine worming/ parasite control. Especially as some of these bugs can be shared with you! So, parasite prevention such as worming keeps you and your cat safe! 

If your cat is regularly vomiting and/ or having diarrhoea, your vet may test their faeces for these bugs to target treatment accurately. Your vet may also suggest an endoscopic exam (a small camera passed into the stomach/ intestines) with or without a biopsy (sampling) to check for some types of bacteria that like to live in the stomach walls themselves (like Helicobacter pylori). Given the test results your pet may then be prescribed antibiotics or antiparasitic medication. 

Dietary indiscretion/ Intestinal blockages 

Some cats like to eat things they shouldn’t, especially string and plastics. These foreign items can get stuck in the stomach or intestines and cause your pet to become very poorly indeed. This is usually an emergency situation. Some cancers can also cause blockages. 

Your vet will likely perform a blood test and some imaging. Usually either an x-ray or ultrasound examination of your pets’ abdomen (sometimes both), to determine the cause of your pets illness. This is usually led by an owners’ history, with a strong suspicion of their cat having eaten something, an item being missing from the house, or some items being found in vomitus but symptoms not resolving. Alternatively, it could be suspected that your cat has a blockage from your vets’ clinical examination and abdominal palpation. Treatment will depend on the cause that is found but will usually involve supportive care such as intravenous fluids and / or the need for a surgery to determine and hopefully treat the cause of the problem. 

Metabolic disease (Diabetes / Hyperthyroidism /Kidney disease / Liver disease / Gastritis / Pancreatitis / Triaditis/ IBS) 

You, as a pet owner, are very important in helping the vet find out why your pet may be unwell. A detailed history of the symptoms can guide a vet to the most likely cause of your pet being sick. For example, if your pet is suddenly drinking a lot more than usual and ravenously hungry but losing weight, your vet may suspect diabetes. A blood test may be performed to look into the function of your pets’ organs and check they are working as they should. Your vet will then guide you as the best way to treat any abnormalities found on the blood test and any follow up that is recommended. 

Diabetes

A disease of the pancreas where either enough insulin isn’t produced, or the body doesn’t respond to it. Once food is digested and glucose is absorbed into the bloodstream, it is unable to reach the body cells, resulting in high levels of glucose in the bloodstream. As the glucose can’t be used as energy, the body looks for other sources and so breaks down fat and muscle; leading to a very poorly cat. Vomiting can be a feature of this disease, especially if ketoacidosis occurs.. 

Hyperthyroidism 

A disease of the thyroid gland where too much thyroid hormone is produced. This leads to an increase in metabolic rate and lots of associated clinical signs; such as a faster heart rate and ravenous appetite. As well as weight loss due to increased metabolism breaking down the food at a faster rate than it can be consumed. Vomiting is often a feature of this disease. 

Kidney or liver disease

Both are more prevalent in the older patient but possible in younger cats due to congenital issues (abnormal organs the pet is born with), toxin ingestion leading to damage of the organ, or cancer. Both the liver and kidneys are, in simple terms, involved in removing waste products from the body. If they aren’t efficiently doing this, waste products build up in the body leading to a very poorly cat. Vomiting is often a response in this disease. 

Gastritis / Pancreatitis / Triaditis / IBS 

These are grouped together as they indicate different parts of the digestive system becoming inflamed, the stomach, pancreas, bowel, or a mixture of them. There are a number of reasons why the organs become inflamed. Depending on the cause, diagnostics and treatment will be targeted by your vet. 

Poisons and toxins 

Ingestion of harmful substances most commonly with cats either plant based (such a Lilies), fluid based (such as ethylene glycol – antifreeze) or animal based (such as toads!) lead to a varying level of illness and consequences from hypersalivation after liking a toad, to possibly full kidney failure from ingesting lilies/ ethylene glycol. The body induces vomiting in an attempt to purge itself of the harmful substance. The key here is recognising risks, eliminating them before ingestion if possible or post ingestion seeking urgent veterinary attention and treatment. 

Cancer 

Cancer can either change the functioning of an organ or lead to a blockage of the flow of digesta. In cats, cancer of the bowel (especially diffuse alimentary lymphoma) is fairly common; however, other cancers may affect other organs, or even change the blood chemistry. Either way, your vet will need to identify the origin of the disease. And then advise you on any action that can be taken or intervention that is necessary. Blood tests and imaging (ultrasound, x-rays, endoscopy or surgical exploration) may be indicated; your vet will discuss the reasonings and benefits of each approach. 

When to contact your vet

If your cat seems unwell, lethargic, has a reduced appetite for more than 24hours or isn’t eating at all or suffers continuous vomiting (more than 3times in 24hrs or regular vomiting for more than 24hrs), if there is blood in the vomit, if your cat is hiding away and demonstrating signs of a painful abdomen, you should seek immediate veterinary attention. 

How will my vet go about diagnosing the problem with my cat 

A detailed physical exam consisting of checking your pet’s mucous membrane colour, abdominal palpation feeling for thickened intestines, pain particularly in the front of the abdomen (pancreatic region), irregular or a change in size of one or both kidneys, enlarged liver, abdominal lumps, lymph node sizes, heart and lung sounds etc. 

Your vet may recommend a blood test, with or without imaging such as x-rays, endoscopy (a camera into the stomach with or without taking samples or biopsies), ultrasonography or even a surgical exploration (“ex lap”) to aid in diagnosis and treatment of your pet. 

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