Why Is My Cat Sick? | Common Reasons & Advice

Cats can be sick quite often, sometimes it’s food they bring up, and other times nothing more than a saliva looking pile. As any cat owner will tell you, their furry friend could probably win a pet Oscar when it comes to being sick – they are very dramatic with it! They have a knack of being sick when you least want them to, or in the most inappropriate place.

But why are some cats often sick? And what is the main cause of vomiting in cats and can it be reduced or stopped? What does a cat being sick indicate and is it dangerous? All these questions and others are answered in this Pets4Homes article.

So, what is vomiting and why would my cat feel sick?

In cats vomiting will happen automatically, the cat will have no control over it – so as much as they may not like it, the brain takes over with what is called the ‘protective reflex’ and will empty all the contents of the stomach. This ensures that there is less of a risk of the cat being poisoned by something it has eaten (and probably shouldn’t have).

The protective reflex is triggered by a part of the brain called the chemoreceptor trigger zone or CTZ. This is the part of the brain that deals with anything nasty in the blood – if it finds anything, such as a poison, then it will stimulate the reflex and nausea and vomiting will occur. It's not just poisoning that can cause the feeling of nausea for the cat, any condition with the gut, or even travelling can also cause them to be sick.

Generally, stomach upsets such as being sick, are less common in cats than in dogs, but there are a vast number of things that can cause a cat to be sick.

Okay, what reasons do cats vomit?

Let’s start with the most common and causes that cat owners (or should that be cat staff?) are usually aware of:

• Travel sickness - ever tried taking your cat to a vet, when all of a sudden there is the sound of them being sick in their basket? Travel sickness is common – in dogs as well – and it’s when the motion the cat feels in their inner ear does not match up with what they are seeing. They start to feel nauseous and are often sick. It is only when the car has stopped does everything return to normal.
• Hairballs sometimes known as fur balls – because of the hooks on a cat’s tongue, when they groom themselves, they can pull out a lot of hair (this condition is especially common in long-haired cats). This hair is generally swallowed and can form a clump in the stomach, which is both irritating and a potential obstruction. It means the cat starts to retch to get rid of the fur ball.
• Intestinal obstructions – anything that can get stuck in the gut, or stops the cat’s food from moving through the digestive system can trigger vomiting. Obstructions can be hairballs, constipation (sometimes caused by hairballs), foreign bodies such as toys that have been swallowed, and cancerous tumours.
• Gastroenteritis, when the cat has eaten something, they shouldn’t have it sometimes causes an upset stomach, this is much more common in dogs, but feral or free-roaming cats can be more susceptible to this. It is usually caused by a gone off piece of food, in a cat it can even a decomposing mouse!
• Infections – intestinal infection such as feline panleukopenia can cause your cat to be sick, bugs such as Salmonella can make them severely ill.
• Inflamed guts, otherwise known as inflammatory bowel disease can cause such discomfort that the cat is sick.
• Simple things such as grass, which cats are well known to eat, can irritate the back of the throat, leading to the gag reflex. This, in turn, will stimulate the CTZ and can cause a cat to retch and vomit.
• It is similar for certain poisons and drugs, the CTZ may be triggered in this scenario, resulting in a sick cat.
• If the cat is on certain drugs, not only can they make them feel sick, they can cause problems with the stomach’s lining and can lead to a stomach ulcer – which in itself can make the cat vomit.
• Medical problems can also cause ongoing vomiting in cats, due to chemical imbalances in the cat's body and blood system. Common conditions include:
  • Kidney failure, otherwise known as renal disease.
  • Liver disease, (hepatic disease).
  • An overactive thyroid, known as hyperthyroidism.
  • Diabetes – diabetes mellitus is quite common in cats.

Can my cat being sick, cause them a problem?

Yes, it can. Especially if the cat continues to have chronic vomiting, which means it is ongoing and they can’t keep anything down. They start to lose two essential fluids, which are water and their stomach acid. In itself losing a large amount of water can lead to dehydration of the cat, which can cause other problems to arise. When the cat loses stomach acid, it means their body has too much alkaline causing a condition called metabolic alkalosis. If this affects the blood, it can start shutting down the body organs and systems. The cat can also lose essential salts.

If this continues or is ongoing for several days, it can cause:

• Shock.
• Organ failure.
• Collapse.
• Heart failure.
• And in severe untreated cases, it can cause death.

How can a vomiting cat be treated?

For general vomiting, where the cause is thought to be the cat has eaten something which is not agreed with it, most vets will advise to not give them any solid food for around 24 hours, allowing the gut to recover. Water must always be available. After the 24 hours, it is generally advised to give a bland diet such as chicken or whitefish, which can help settle things. The vet may give an antiemetic (a medication to stop the sick feeling) or a powder for their water to replace electrolytes, salts, and minerals.

More severe cases may need further tests to find out why the cat is being sick. Tests can include:

• X-rays
• Scans
• Blood tests
• Endoscopy
• Faecal tests

In cases such as this, the cat will normally be hospitalised and put on a drip to manage the condition and reduce dehydration.

In all, a vomiting cat can usually be treated successfully and the condition minimised. It is also worth remembering that not all conditions can be cured, if the cat has kidney failure for example, the condition can be managed if diagnosed in the early stages. If you have a cat that is sick more than normal, it is worth getting them looked at by a vet.