High temperature (fever) in cats

Black cat on white background


If your cat has a high temperature (fever), it usually means something is wrong. You may notice that they are hot to touch, obviously unwell, eating less, drinking less, have low energy or just don’t seem themselves.

There are many possible reasons for a fever to develop ranging from minor to much more serious. Your vet will examine your cat and may run some tests to work out what the problem is.

Treatment for a fever varies depending on the cause.

What does a high temperature mean?

A cat’s normal body temperature ranges between 38-39°C, if it rises above the normal range your cat is likely to feel unwell and become low in energy (lethargic).

Your cat may feel hot to touch especially their feet, ears or face, they may hide away and not want to eat. Your cat may also shiver and start to breathe more quickly than usual.

A high temperature can be caused by many different conditions ranging from minor to serious.


Infections and abscesses

Infections and abscesses are a very common cause of high temperatures in cats.

Cat bites are the most common cause.

Unknown Pyrexia of unknown origin

Pyrexia of unknown origin’ is a condition which causes a high temperature with no obvious cause.

Pain and inflammation (swelling)

Any type of pain or inflammation such as arthritis or bladder inflammation can raise a cat’s temperature.


Some insecticides and slug pellets cause muscle tremors which can cause a cat to overheat.

Heat stroke

Cats left in cars or stuck inside hot spaces in summer can get heat stroke.


Cats stress very easily and this can raise their body temperature.

Medicine reactions

Medicine reactions can cause a high temperature.


If your cat is overweight, it’s much harder for them to lose body heat.


Cancer can cause a high temperature in a cat, however, there are likely to also be many other symptoms.

Feline Leukaemia Virus (FeLV) is a common cancer in young cats that can be prevented by vaccination.

Pyrexia of unknown origin (PUO)

‘Pyrexia (which means high temperature) of unknown origin’ means your cat has a high temperature with no obvious cause. This is a tricky condition to treat. It can take some time, and several different tests before a cause is found and the correct treatment is started. Often the cause isn’t found but their high temperature gets better with medical treatment.

When to contact your vet

You know your cat best, you are concerned that they have a high temperature book an appointment with your vet.

Published: December 2018

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Written by vets and vet nurses. This advice is for UK pets only.

Illustrations by Samantha Elmhurst