What Causes a Cat's Personality to Change?

What Causes a Cat's Personality to Change?


When it comes to personality and resulting behaviour, we all tend to expect our cats to stay much the same throughout their lives. But sometimes this does not happen. For instance, an active cat may suddenly slow down and want to sleep a lot, a previously friendly cat may become withdrawn and nervous or vice versa, and a well behaved cat might suddenly start behaving badly. These personality or behaviour changes can be rather worrying for an owner who does not understand what is happening. So what can cause a cat's personality to appear to change? Well, there are a number of possible reasons, so let us take a look at some of them.

Personality Changes as a Cat Gets Older

Most cats change as they age, just as humans often do. Previously active cats probably tend to slow down, which means a cat who always wanted to be outside hunting in his youth may turn into a friendly lap cat when he is older. Some cats suffer from cognitive decline in their later years, and forget things like proper use of the litter tray, or even forget where they are. This can upset them, so that a previously well adjusted and happy cat becomes nervous, anxious, and withdrawn. Some sociable cats may want to be alone more of the time, and conversely, some older cats become more friendly and dependent on their owners.

These changes may just be typical of getting older, but don't necessarily assume that this is the case. It could be worth mentioning to the vet during your cat's annual check-up, as some personality changes may be indicative of illness. Cats are very good at hiding the fact that they are ill, so it is always worth mentioning changes like this.

Spaying and Neutering Causing Personality Changes

When you have your cat spayed or neutered, this could change their personality; indeed it very often does due to the resulting hormonal changes. Male cats in particular can go from wanting to fight and chase members of the opposite sex, to being much more laid back and affectionate. They may stop demanding to always be off in the outside world, and be happy to stay at home and relax. Female cats probably change rather less, but they will not be coming into season and looking for a mate at regular intervals. So they too may appear to be more relaxed and friendly. This is all perfectly normal, and you do not need to worry about it.

Personality Changes Due to Stress

Cats do not really like change, and even small changes in their home life can greatly upset them. So have you recently moved house, had a new addition to the family whether human or feline, or made some other household change? If so, your cat may be feeling stressed, and this can show itself in behaviour changes and even an apparent change in the cat's personality. This can even happen in response to apparently small changes, such as having a new carpet installed, change in cat food type or cat litter brand, or minor repairs being done in the home. All of these may upset a cat, who may not seem disturbed, but could behave differently, lose its appetite, or become aggressive. It is worth trying to find out what has upset your cat, so that you can do whatever is possible to minimise the stress. You may also find that pheromone sprays such as Feliway, or herbal compounds such as Pet Remedy, help your cat to feel better and cope better with the changes. But if none of these things help, it could be worth checking with your vet, both to find out what could be done to help the cat, and also to ensure that there are no underlying medical problems.

Has a Particular Occurrence or Event Upset Your Cat?

As well as generalised changes causing stress, sometimes one particular occurrence or event can upset a cat enough to change its personality for quite some time. If the cat has a road accident, gets attacked by a dog, or even something less major than this, it may disturb the cat enough to cause fairly long term personality changes. Some cats appear to shrug off such events, but some seem to have very long memories and cannot do this. A friend of mine had a cat who was roughly handled at a cat show, and for a long time afterwards was quite wary of strangers. Similarly, one of my cats was seriously ill when he was young, and went from being a confident cat who loved everybody, to a much more wary feline who wasn't sure whom he could trust. Changes such as this may be fairly short lived, or could last for years, even the cat's whole lifetime. Sometimes there is little the owner can do except offer love and reassurance, and accept the cat for how they are now.

Random Behaviour Changes Without Any Obvious Reason

Finally, some cats appear to change for no obvious reason, or none that can ever be discovered. Sometimes the owner is delighted, particularly if a standoffish cat suddenly becomes more friendly. But if the reverse occurs, the owner may not be quite so pleased. If your cat really seems to change, it is always worth having a word with your vet. But you may need to accept that there is no obviously cause.


As you have probably gathered by now, there can be all sorts of reasons for a cat's personality change, some of them quite normal, some more worrying. If your cat seems to change in personality or behaviour, it is always worth seeking advice from your vet, in case it signifies illness or something similar. But if the cat is given a clean bill of health, then don't worry too much. Just accept that cats, like people, are not necessarily the same throughout their lives. And no matter how much they change, we will still love them!



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