Vomiting and diarrhoea in cats

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Vomiting and diarrhoea in cats

Cats often vomit or develop diarrhoea, when should we treat? The reason for the vomiting or diarrhoea may be simple, such as a hairball, however the cause could be more serious. Whether the symptoms stop on their own, or whether your cat needs to see a vet, will depend on how he or she is in themselves and what the vomit or diarrhoea looks like.

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Signs of vomiting and diarrhoea

  • Nausea before the event: drooling, lip licking, excessive swallowing
  • Vomit: strong abdominal contractions and head nodding. Note the colour, volume, frequency, and when the last meal was
  • Diarrhoea: note the frequency, colour, consistency and look for signs of blood
  • Fever
  • Pale or cold gums, occasionally their gums or the whites of their eyes might look yellow
  • Quiet or lethargic
  • Weight loss
  • Poor appetite or refusing to eat

Causes of vomiting and diarrhoea

The reason for vomiting or diarrhoea is often due to irritation or inflammation of the stomach or intestines. Common causes include some viruses (similar to human gastroenteritis disease) or that your cat may have eaten something inappropriate (similar to human food poisoning). Other reasons to consider are a foreign body that obstructs the intestine, intestinal parasites, poisoning, sudden dietary changes, salmonella (most commonly seen in Spring and Winter in outdoor cats that come into contact with birds), infection with feline parvovirus (feline distemper), pancreatitis, side effects of medication, or inflammatory gastrointestinal disease (similar to human IBD). Some cats may lose weight and become thin.

In acute cases of vomiting or diarrhoea it is not always possible to identify the cause. Often, these episodes will resolve by themselves or with supportive treatment. This typically involves feeding a bland, easily digestible diet (see suggestions below), feline probiotics and electrolytes. However, for more severe cases, and for those that do not resolve quickly, it is important to seek veterinary treatment without delay. Treatment at the clinic may involve intravenous fluid therapy, anti-sickness medication and pain relief if required. Depending on the clinical signs, it may be necessary to take blood samples as well as x-rays or an ultrasound scan of the abdomen, to try to identify the underlying cause.

If your cat has recurrent episodes of vomiting and or diarrhoea it is advisable to make an appointment with your vet who will examine their stomach and intestines. Recurrent vomiting or diarrhoea may indicate that there is an underlying disease that needs treating. If your cat vomits more than 1-2 times a month, even if it is hairballs, then you should seek veterinary advice.

Pancreatitis is a disease where there is inflammation of the pancreas. It is not yet fully understood why pancreatitis occurs in cats and often there is no known underlying cause for the disease. Your vet might recommend a blood test to check your cats’ pancreas and they might also ultrasound their abdomen to assess the organ as well.

Feline triaditis only occurs in cats and is the simultaneous inflammation of three different organs: the pancreas, liver, and intestines. Triaditis is the result of three conditions occurring simultaneously. It is a poorly understood condition and often the original cause can not be determined.

What can you do to help your cat at home?

Is your cat bright, alert and behaving normally? If you have not seen blood in the vomit or diarrhoea, then you can often provide some supportive treatment at home:

  • Do not starve your cat: withholding food is not appropriate because they risk getting a life-threatening liver condition called hepatic lipidosis. Research also shows that the gut needs contain food to start the healing and recovery process
  • Hydration: your cat must have access to clean fresh water at all times
  • Highly digestible diet: offer this in small portions little and often. For example, a prescription intestinal diet, such as Purina EN, or boiled rice or potato with cooked white fish, chicken fillet, turkey or egg (feed ⅓ protein to ⅔ carbohydrate)
  • Electrolytes and probiotics: use these feline supplements alongside their diet, following the manufacturer’s instructions. For example, Oralade GI Support Rehydration Fluid or Royal Canin Rehydration Support
  • If your cat is an outdoor cat, keep them indoors, as long as this does not cause them distress, where they can be supervised for a few days so that you can monitor any vomiting or diarrhoea

A suggested feeding schedule:

  • Day 1: feed the recommended daily amount divided into 6-8 portions
  • Day 2 and 3: feed the recommended daily amount divided into 4-6 portions
  • Day 4 and 5: feed the recommended daily amount divided into 3-4 portions
  • Once your cat has been normal for a couple of days you can gradually re-introduce the usual food

Typically, cats need 50ml of liquid per kg of body weight per day. This means about 200ml for a cat weighing 4kg.

Treatment of diarrhoea and vomiting

The vet will adapt the treatment depending on how sick your cat is and what symptoms they are showing. Blood samples may be taken to assess how dehydrated your cat is, the level of red and white blood cells, and whether internal organs are affected, including the liver and kidneys. Electrolyte levels (sodium, potassium, chloride) will be checked, which are used to direct the appropriate fluid therapy. X-rays and/or an ultrasound examination may be indicated if your cat has abdominal pain or a potential foreign body.

If there is a clear underlying cause this can be treated appropriately. Otherwise, symptomatic treatment will be provided to reduce the secondary effects of nausea and dehydration. There is rarely any reason to give antibiotics to cats with vomiting and diarrhoea, unless there are signs of septicaemia (blood poisoning), as they can disrupt the normal gut flora further.

How can I prevent my cat getting diarrhoea and vomiting?

Avoid giving your cat very salty, spicy or fatty foods, as this may increase the risk of an upset stomach. In order to reduce the risk of problems associated with dietary changes, we recommend introducing new food gradually; you can try introducing new food over at least seven days and monitor for any intestinal disturbances. If your cat is sensitive to stress, or a course of antibiotics has been prescribed, then you can feed a probiotic supplement to help reduce the risk of intestinal disturbances. During periods of stress, it may also be helpful to use a soothing pheromone spray or plug-in adapter (eg Feliway).

It may be useful to keep probiotics and electrolyte supplements at home, together with some chicken or white fish in the freezer, in case of an emergency. If you know that your cat catches mice or birds then you can send in a stool sample for analysis periodically to see if they need worming. If possible, try to stop them having access to the bird table and the surrounding area to reduce the risk of salmonella. Your cat should be vaccinated against feline parvovirus (feline distemper) annually. Parvovirus can, among other things, cause life-threatening stomach and intestinal problems in cats.

Ensure that your cat is wormed frequently. Roundworms are extremely common in kittens. Follow the link to our article on kitten care. Kittens can be infected through the mother’s milk. It should be assumed that all kittens are infected and therefore worming should be started at a young age. We recommend treating your kitten for roundworms every 2 weeks, from 3 weeks of age until 12 weeks of age, and then monthly until 6 months of age. A regular worming program to suit your cat as an adult should then be discussed with your vet. Tapeworms are usually only a problem in older cats. Kittens with fleas should be treated for tapeworms, as fleas can transmit tapeworm larvae. We recommend treating adult cats (over the age of 6 months) every 1 to 3 months with a product that is effective against both tapeworms and roundworms. Ask your vet or make an appointment with one of the FirstVet vets to discuss worming your kitten or cat.

When is it time to visit your vet?

If you notice any of the following clinical signs then your cat should be seen by a veterinarian:

  • Vomiting several times per hour or continued vomiting
  • Cannot keep water down
  • Blood in the vomit or diarrhoea
  • Increasingly lethargic
  • A painful abdomen
  • Inappetent or anorexic
  • Dehydrated
  • If you know or suspect your cat has swallowed something that could damage the intestine, such as a ribbon or thread: don’t try to pull the thread out as this can cause damage lower down the intestinal tract
  • If your cat does not improve despite being given supportive treatment at home for 1-2 days (young kittens and old cats should see a vet sooner)
  • If your cat has chronic vomiting (once or twice a month)

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Published: 15/10/2019
Last updated: 02/03/2022

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