Vomiting and diarrhoea

Vomiting and diarrhoea are common in cats. Both are symptoms of other conditions rather than diseases in their own right and there is a vast range of cat diseases in which diarrhoea and/or vomiting may occur. In many cases the problem may be successfully treated without ever pinpointing the actual cause. However, the information that you give your vet may be vital in deciding whether the case is serious enough to need further detailed investigations.

Diarrhoea occurs when the normal functioning of the large bowel (intestine) is disturbed. The large bowel is responsible for absorbing water from the gut and if it does not do this properly, very liquid faeces (droppings) are produced.
Vomiting occurs when stomach juices are expelled from the mouth. It is important to distinguish vomiting from regurgitation. Regurgitation only occurs after a meal and the material will have visible lumps of undigested food which are often eaten again.
The causes of both diarrhoea and vomiting include viral, bacterial or parasitic infections; changes in diet, stress or excitement, poisonous drugs or chemicals, blockages or damage to the digestive system or other body organs.

It is often difficult to know that your cat has diarrhoea if it goes to the toilet outside the house and immediately covers up the faeces (droppings) with soil. But the problem becomes obvious if it uses a litter tray, if it has an accident indoors or in long haired cats whose back ends can become soiled with diarrhoea. A cat will readily vomit indoors.

Both diarrhoea and vomiting occur as short lived (acute) conditions lasting 1-2 days which will often clear up on their own, and as long-term (chronic) problems which are usually more serious. If your cat does not appear to be in distress or be losing weight, all you may need to do is to withhold all food for a day and then give your cat small amounts of cooked fish, chicken or some other food which is easily digested. Make sure clean fresh water is available but do not give milk.

If vomiting or diarrhoea is continuous for more than 24 hours, despite starvation, your cat could become dangerously dehydrated and should be taken to your vet.
Contact your vet sooner if a kitten is ill (because they get dehydrated more quickly than adults), if there is blood in the vomit or diarrhoea, if the faeces (droppings) are of a black and tarry appearance.
Never treat your cat yourself with drugs from your own medicine cabinet because some human drugs are poisonous to cats.

Your vet will manage acute diarrhoea or vomiting by starvation unless your cat is dehydrated then it may be given fluids and essential minerals by mouth or injection. Your vet may not give antibiotics because bacterial infections are one of the rarer causes of these problems and because ‘good’ bacteria are always present in a normal gut, antibiotics (which kill these too) could actually make the problem worse.

Your vet will ask you questions about your cat, such as:

  • Is your cat ill or depressed?
  • Has your cat eaten any unusual foods?
  • Is there anything unusual about the colour and smell of the your cat’s faeces or vomit?
  • When and how often is your cat being sick or having diarrhoea?
  • Are there other cats in the household and have these also been affected?
  • Has your cat been hunting or scavenging left over human food?
  • Has your cat been given any medical treatment or been exposed to any potential poisons?
  • Think about these questions before going to your vet and see if you can identify any possible reason why your cat may be ill.

If the illness continues for more than a couple of days it may be necessary for your vet to carry out a range of tests to find out the cause of the problem. A small sample of your cat’s faeces will be examined for bacterial infections or parasites in the gut. Blood tests may also be taken to check for infection, kidney or liver disorders.
An x-ray may be needed to see if there is anything abnormal in the gut. Sometimes your vet will put an endoscope into your cat’s stomach and intestine to try and see the cause of the problem, and a small biopsy sample of intestine may be removed for examination.
Digestive upsets are unpleasant for you and your cat but in most cases your cat will be better within 1-2 days. If your cat is not improving after 24 hours make an appointment with your vet for further advice.

Vomiting and diarrhoea
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