Why has my cat lost his appetite? When a vet is required.

I have put off answering this question because it is such an enormous topic and of course it is all to do with a veterinarian’s work, for which I am unqualified. But I feel that I’m qualified to at least address the issue while referring to excellent references. Sometimes loss of appetite in cats is called feline anorexia. This is a very common question. It is worrying for a cat owner when their cat stops eating and starts to lose weight. You will have to decide whether your cat has lost his appetite because he has become disinterested in the food that you are providing, perhaps because you are providing the same food all the time.

Loss appetite in cats
Loss appetite in cats. Image: PDSA.
Two useful tags. Click either to see the articles: Toxic to cats | Dangers to cats

Variation is important and it should be high quality food. But if you sense that your cat has lost his appetite for a health reason, you are going to have to contact your veterinarian immediately and make an appointment. That advice comes from any good veterinarian because a loss of appetite is a general symptom of being ill, possibly seriously ill.

RELATED: Lethargic cat with dry mouth and loss of appetite

You can’t really stipulate all the illnesses that cause a loss of appetite but in general terms it will be: infections and abscesses, injuries and trauma, mouth pain or gastrointestinal conditions, dehydration or anaemia. That advice comes from Dr. Bruce Fogle DVM, a top UK veterinarian and author. One reliable website states that a respiratory disease can affect a cat’s sense of smell and therefore their food will not be attractive because cats depend upon their sense of smell when eating to decide if the food is palatable. I agree this.

See a vet asap if these are present

There are other behavioural changes which indicate a health problem which is serious enough to demand that you take your cat to the vet immediately and these are as follows according to Dr. Bruce Fogle:

  • Abnormal breathing which might indicate the following illnesses: fluid in the chest cavity, heart failure, asthma, lung disease and heat stroke;
  • Unsteady on her feet which may be caused by poisoning, neurological disorder, ear infection, spinal trauma, pelvis fracture and brain trauma;
  • Bad breath indicates kidney disease, diabetes mellitus, liver disease, tooth abscess, periodontal disease, intestinal problems and cancers of the mouth;
  • Loss of appetite – I have mentioned this above;
  • And finally, drinking more than usual are signs of diabetes, kidney failure, lower urinary tract disorder, urinary tract infection, worm infection and overactive thyroid.

Some more diagnostic checks

With respect to abnormal breathing, this might include breathing out harder than breathing in or vice versa, breathing faster than normal, breathing heavily from the belly as opposed to the chest and panting unexpectedly.

Other general signs of being unwell might include vocalising more or less than normal, making unusual sounds, scratching more than normal, going to the toilet more or less than usual, a glazed look to their eyes and hanging their head also may be signs of an undiagnosed illness which can be combined with the above symptoms, all of which require seeing a veterinarian.

Here are some quick checks that you can perform on your cat if you think that they are unwell. The information comes from Dr. Bruce Fogle again.

  • You can check your cat’s circulation by checking “capillary refill time”. This helps to check blood circulation. You lift your cat’s upper lip and press your finger against the gum tissue. Do this briefly and when you remove your finger it leaves a white mark on the gum. Watch how long it takes for the pink colour to return. It should take around a second to become pink again and if it is slower, it could mean dehydration, heart failure or shock.
  • You can check for dehydration by grasping the scruff of your cat’s neck and pulling it up. The skin should spring back immediately. If your cat is dehydrated it will take longer for the skin to fall back into position. The worse the dehydration the longer it takes.
  • You can check your cat’s gums to ensure that they are pink if they are pale or it white may indicate anaemia or shock. Blue gums indicate that there is not enough oxygen in the bloodstream and yellow gums indicate jaundice caused by malfunctioning liver. If the guns are bright red, it can indicate carbon monoxide poisoning or heat stroke. My thanks to Dr. Bruce Fogle.

Personal experience

On a personal level, one of my cats who passed many years ago, a female, developed kidney disease at the age of about 16 and by the age of 18, one day, she looked up at me after I had given her food and told me with her eyes that she could no longer eat it. To me, it was a clear signal that it was time to say goodbye. If an old cat stops eating it is that kind of signal in my view. You should know by then what disease(s) they have. It may well be kidney disease because this is such a common disease in elderly cats.

Oral health

My personal view on loss of appetite is that one very common disease is perhaps most likely to be the reason if your cat is in otherwise good health and this is mouth disease. Specifically, I’m referring to gum disease (periodontal disease). It is very difficult to monitor this because it means forcing your cat’s mouth open and inspecting the inside of their mouth which is something that cat owners will put off. This is all the more reason why an urgent visit to a veterinarian is required. Bad oral health is often accompanied by bad breath and this may provide a good signal as to what the problem is but kidney disease is also linked to bad breath and mouth disease.

Below are some pages on oral health.

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Useful tag. Click to see the articles: Cat behavior

Note: sources for news articles are carefully selected but the news is often not independently verified.
Useful links
Anxiety - reduce it
FULL Maine Coon guide - lots of pages
Children and cats - important
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