What do to when your cat becomes aggressive out of the blue

Every cat has its own temperament, which can change according to its mood. But what should you do when your feline's bad mood turns into real aggression?

Is your cat aggressive all of a sudden? Read these helpful tips to find out why your cat may have become quarrelsome and how to deal with an aggressive cat.

Recognize aggressive behavior before the cat lashes out

Cats' moods can change quickly.
Cats' moods can change quickly.  © Unsplash/MusicFox Fx

A second ago everything was fine, but now suddenly your kitty is hissing and swatting at you. You're right to ask why the cat has suddenly changed its tune.

But don't worry! There is reason behind this sudden change in temperament. After all, cats are never just randomly aggressive

A cat that becomes aggressive seemingly out of the blue can be a real problem, especially when children or visitors come into close contact with the animal, making it all the more important that a cat's caregiver knows what to do and how to react.

Dog's adorable response to orphaned kitten melts hearts on TikTok: "This was his kitten"
Cats Dog's adorable response to orphaned kitten melts hearts on TikTok: "This was his kitten"

How do you know if your cat is getting agitated?

Typical signs of aggressive behavior in cats:

  • it arches its back and its fur stands on end
  • its eyes are wide open
  • it stares intensively at its perceived opponent
  • its pupils are dilated
  • its ears are pulled back towards its head
  • it growls or hisses
  • its mouth is wide open
  • it whips its tail around frantically

If a cat is displaying one or more of these signals, it is in an aggressive mood, and you shouldn't agitate it any further.

But what makes a cat act this way? Here are eight reasons why cats become aggressive.

1. The cat is in pain

Cats in pain tend to react aggressively.
Cats in pain tend to react aggressively.  © Unsplash/niklas_hamann

Cats can become aggressive because they are in pain. Just like dogs, cats are very good at masking their pain.

But if your cat suddenly becomes irritable, it may indicate that there's something awry with your otherwise healthy pet.

Pain resulting from disease, abscesses, parasites, or tumors may be triggering the cat's change in demeanor.

If you can't figure out what's causing your cat's discomfort or disturbing disposition, it's a good idea to take it to the vet.

A more thorough examination that includes blood work or X-rays will quickly reveal if there is anything wrong with your pet. If everything seems normal, then at least you know its not pain that's making your cat act out.

2. The cat doesn't want to be cuddled or petted

Cat's don't always want to be petted.
Cat's don't always want to be petted.  © Unsplash/Jesse Borovnica

If a cat gets aggressive when you try to pet it, then its bad behavior might be triggered by human touch.

The cat may be trying to express its displeasure with its teeth or a swat of its paw.

If you've already ruled out pain, then this might be what's causing your feline's aggression.

Many cats don't like lots of cuddles or pets, and sometimes people misinterpret the signals cats give. If, for example, a cat jumps on your lap, you might think that it's coming by because it wants to be petted.

However, it is quite possible that the cat isn't interested in your attention. It might just be looking for a comfortable place to doze. When you reach toward the animal, it may feel attacked and react accordingly.

But this kind of aggression is easily prevented. All you need to do is watch the cat's body language. Every displeased cat sends a series of warnings before acting aggressively. If your cat starts to display one of the signs of aggression, then you should leave the it be.

3. The cat is scared

Cats need a place to withdraw to.
Cats need a place to withdraw to.  © Unsplash/Thomas Bormans

Every cat needs a certain amount of freedom to feel comfortable.

They also need their very own place to retreat.

Then if they are frightened by something unfamiliar, they will feel like they have a safe place to go back to.

If they don't have their very own safe space, their fear often turns into aggression. If cats feel cornered and therefore unsafe, then their "fight" mechanism kicks in because they don't feel like they have a place to flee.

As a cat owner, you should keep an eye on your pet. If it looks agitated, make sure it has a way out of an overwhelming situation. These situations can happen, even when your cat is familiar with the people around it.

4. The cat is defending itself

It's not a good idea to tease cats.
It's not a good idea to tease cats.  © Unsplash/Makhmutova Dina

It is also not uncommon for cats to react to perceived aggression with violence.

If a cat is used to dealing with violent behavior from other animals or humans, then it might react to any seemingly aggressive behavior on your part with more aggression.

That's another reason why it is really important to use positive reinforcement when training your cat as opposed to punishment, especially corporal punishment.

If you want to keep your cat's tendency towards aggression as low as possible, patience and a loving approach are essential.

5. The cat is playing

Don't teach cats that biting or scratching is acceptable behavior.
Don't teach cats that biting or scratching is acceptable behavior.  © Unsplash/Humberto Arellano

At times, the cat's seemingly aggressive behavior may just be related to how the cat plays.

Should the kitty repeatedly bite and scratch its playmate during a game, you need to intervene.

This kind of behavior is learned and should be discouraged.

It is possible to train the cat not to engage in this kind of behavior, for example, by making a sound to make it clear the cat is causing pain. If the aggressive behavior appears, you can also teach the cat that it is unacceptable by stopping the game, ignoring the cat, and leaving the room.

6. The cat is old and easily annoyed

Older cats prefer peace and quiet.
Older cats prefer peace and quiet.  © Unsplash/Nathan Fertig

If your cat happens to be a bit older, it is not uncommon for it to show increasingly aggressive behavior.

Just like humans, older cats are more sensitive to pain than their younger counterparts.

Senior cats also tend to suffer from arthritis, which causes discomfort when walking and jumping. Even petting can suddenly become unpleasant.

If you want to do something good for your cat in old age, you should make sure that it has peace, quiet, and lots of good spots to hide. You should also be gentler when handling your cat.

7. The cat is stressed by change

Changes like a new roommate, a move, or renovations can make cats super aggressive.
Changes like a new roommate, a move, or renovations can make cats super aggressive.  © Unsplash/Tran Mau Tri Tam

If the cat suddenly shows a new, more aggressive behavior within a fairly short period of time, a change at home might be to blame.

Have you brought a new pet into the family, or has one of their dear friends passed away?

Is there a new baby in the house? Or a new partner?

Maybe the kitty cat feels threatened by a fellow animal in the house or in the neighborhood?

Generally speaking: has something changed that could be a stressor for your feline friend?

If this is the case, you should try to keep stressors to a minimum in your cat's environment. If you can't do so, try to give your cat an extra place to withdraw when it's upset.

How to deal with an aggressive cat?

You can nip aggressive behavior in the bud if you know what inspired it.
You can nip aggressive behavior in the bud if you know what inspired it.  © Unsplash/Paul Hanaoka

So what to do if the cat is suddenly aggressive?

Here are some useful tips how to calm an aggressive cat:

1.) Offer it a place to withdraw like a hiding place or an elevated perch.

2) Keep your cat busy, and help it maintain a healthy mental and physical balance.

3.) Be loving, patient, and calm with your cat, and avoid using aggressive cues during training.

4.) Leave an aggressive cat alone. Don't try to restrain an angry kitty or bend it to your will.

5) Reward good behavior, and ignore your cat's undesirable behavior and tantrums.

6) Take your cat to a veterinarian for a check-up to make sure it isn't experiencing any physical pain.

7.) Watch your cat's body language carefully to avoid provoking aggressive behavior.

Cats always have a reason for acting aggressively, and it's a human's job to recognize what's spurring them on. But you don't need to spring into immediate action if a cat suddenly gets tense. First, see if giving your furry friend a little peace and quiet will help it calm down on its own.

Cover photo: Unsplash/MusicFox Fx

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