Skip to main content

Why is my cat aggressive all of a sudden? We have answers

Here's what's behind sudden cat attacks

Scary striped cat hissing
Radysh / Shutterstock

You’re just sitting on your couch, scrolling through your phone, and looking at old photos of Grumpy Cat (RIP). Out of nowhere, your cat jumps on you — and it’s not to cuddle. Their claws are out, and they’re hissing. Then, they go in for a bite.

After muttering a few words you can’t say in polite society, you may wonder, “Why is my cat aggressive all of a sudden?”

After all, you got up on your cat’s terms — at 5 a.m. — and fed them. The litter box is clean. If your cat is usually sweet or neutral towards you, sudden aggression may catch you off guard. You may also worry. Your kitty may be a fraction of your size, but infected scratch marks and bites can cause cat scratch fever, which may lead to flu-like symptoms.

In other words, you’ll want to figure out what triggered the episode so you can avoid it in the future. Let us help you play detective.

a gray cat with green eyes on a black background
iqbal bamarouf / Shutterstock

Why did my cat attack me for no reason?

Cat aggression happens more than you may think. Behaviorists say it’s the second-most reported behavioral challenge they see in kitties. You may believe you’ve done everything right — and you are certainly trying your best — but there’s usually a reason behind it. A few common reasons for cat aggression are:

  • Play. Some cats didn’t spend much time around their littermates — perhaps their mother abandoned them. As a result, they may try to play rough by hiding and stalking you before pouncing on you.
  • Fear. Scared cats can become aggressive as a means of protection. Your kitty may have heard a loud noise, or perhaps they do not want to get in their kennel to go to the vet.
  • Petting. Petting-induced aggression occurs when a cat doesn’t enjoy those snuggle sessions as much as you do. It’s unclear why some felines display petting-induced aggression, but it can rear its ugly head if the cat is overstimulated or during grooming sessions.
  • Redirected aggression. It may not have been anything you did at all. This type of aggression happens when the cat can’t take its aggression out on the direct source, like a stray kitty in the backyard, so you become the scapegoat.
  • Pain. Sometimes, cats become aggressive if they are in pain. They may hiss, especially if you touch the area that hurts.
  • Territory. Cats have their spaces. If you infringe on a spot they covet, they may become aggressive.
A calico cat with her ears flatten glares at a gray and white cat.
Gurkan Ergun / Shutterstock

Why did my cat get randomly aggressive?

Though cat aggression is common, it may be rare for your pet. An attack can feel random, but your fur baby may have been sending you signals of their displeasure for a while. Could you possibly have missed one of these warning signs?

  • Dilated or constricted pupils
  • Stiff stance and tail
  • Direct stare
  • Growling, howling, or yowling
  • Raised hackles
  • Bushy tail
  • Crouching
  • Tucked head
  • Retracted whiskers

Keep an eye on your pet’s body language moving forward. If it continues to happen with seemingly no warning, you’ll want to visit your vet to see if the pet has an underlying condition causing sudden aggression.

a gray and white cat yawning
itsfahran / Shutterstock

How do you stop sudden aggression in cats?

You love your cat and can forgive their transgressions, but understandably, you want to nip this aggressive behavior in the bud. Here are some ways to do so:

  • Distract the cat. Aggression isn’t always so sudden. If the cat displays signs of aggression, try throwing something like a beloved toy toward them to redirect their attention.
  • Play with them. Sometimes, bored cats can become overstimulated as they attempt to entertain themselves. Keeping them entertained, such as through play, can prevent sudden aggression and enhance your bond.
  • Give them space. You probably have a safe space to go when you are feeling stressed. Your cat deserves the same. A cat cave, window perch, or tall tree can allow them to feel secure. Also, make sure they have their own place for their food.
  • Visit the vet. Your cat may have pounced because they aren’t feeling well. A thorough vet exam can rule out — or help catch — any conditions.
  • Call a pet behaviorist. A behaviorist who specializes in cats can help you identify what’s triggering your cat’s aggression and give you tips to help Kitty cope.
Grey and white cat eating catnip out of a plastic bottle
Creative Cat Studio / Shutterstock

Will catnip calm an aggressive cat?

If your cat pounces, it might be a little too late to reach for the catnip, but supplements can help manage kitty anxiety. Some pet parents prefer treats with catnip and CBD for best results (make sure to purchase from a reputable source). When your sweet pet starts to seem nervous or you know in advance that there will be a trigger, try out a few different options to see what sticks. It’s possible your feline will have an obvious preference or that you’ll notice a big difference. Still, helping your cat deal with her symptoms isn’t a substitute for diving into the deeper underlying causes.

An orange cat meowing
Didgeman / Pixabay

Our final thoughts on aggressive cat behavior

If your usually sweet feline attacks you unprovoked, you may wonder, “Why is my cat aggressive all of a sudden?” The truth is, cat aggression often isn’t random, even if it feels that way to you. Cats typically display signs they’re upset about something before they attack. Body language cues include a change in pupil size, crouching, direct stares, and a stiff posture and tail.

There are several reasons for cat aggression, including fear or pain. Try distracting the cat with a favorite toy when you notice signs of irritation. Giving them space and playing with them can also help reduce stress. If you’re unsure what’s going on, take your kitty to the vet. They may be sick or in pain, and the aggressive episode was their way of trying to tell you since the two of you don’t speak the same language.

Editors' Recommendations

BethAnn Mayer
Beth Ann's work has appeared on and In her spare time, you can find her running (either marathons…
Can cats see in the dark? We separate fact from fiction
Cats have night vision far superior than our own, but they still need light to see
A cat stares into the camera

When something goes bump in the night, you might wake up in a panic, only to realize it's just the cat. These beasties are well known for being up and about in the wee hours of the morning, ready to play, hunt, and eat. While it's true that cats love nighttime, they aren't actually nocturnal. Instead, they exist in an in-between state as crepuscular, meaning your feline will love dusk and dawn most. So, if they aren't actually night owls, can cats see in the dark? We break down what cat vision really looks like.
Can cats see in the dark?

Almost all of us can see something in the dark, but night vision varies considerably among different animals. Owls have particularly good night vision, while humans less so. Cats see about six times better than people at night, which helps them hunt successfully at twilight, in the wild, or from your backyard. But it's inaccurate to say they can see in pure darkness. Instead, kitties have special eyes that allow them to observe a lot more in low light. These are the three main ways cats see better at night.
Smart design
Cat eyes look totally different from human ones, and they are. Feline orbs have special qualities designed to help them hunt in near darkness, such as a curved cornea and large lens (we'll get into what's up with the pupils next). You may have heard of rods and cones, the parts of the eye that help us see light and color, among other things. Our furry friends have more rods and so see more light, and therefore, need less of it (by contrast, we have more cones and observe more colors). Lastly, cats have something called a tapetum that reflects light to the retina. While you may never have heard this term, you've definitely witnessed it in action — this is why cat eyes glow in the dark.
Pupil dilation
When the lights go off, our pupils get bigger, and it's the same with cats. However, our pet's pupils can go from a small vertical slit to a massive globe. As the eye grows larger, it does lose some clarity, otherwise you might expect to find your animal's eyes constantly at full blast. Generally, during the day, their pupils will show up as a thin line for maximum focus and then dilate as needed in dim-light situations. And the growth is an enormous difference, up to 300 times the size of their eye at its smallest.
Myopia is the fancy word for near-sightedness or the ability to see up close but not far away. Many humans wear glasses to improve their vision, but unfortunately, cats don't ever see as well as we do at a distance. The little buds have a wider frame of vision, but everything would look a bit blurry if you adopted their eyes temporarily. In a competition for who can spot a tiny movement, like prey burrowing in the grass, the cat would win.
How cats see the world around us

Read more
Why do cats like boxes so much? It’s not just because they’re weird
Why are some cats obsessed with cardboard boxes?
Cat sitting inside of a cardboard box

Cat owners have all been there: You order your cat a new cat bed, cat tree, or other item that comes packed in a box. When you unpack the item, your cat inevitably plays with the box more than he uses the item that came with it. This adoration of boxes is plenty common in cats, but it also seems a little odd.

Boxes are basic; there's nothing especially exciting about them — or at least that's what you might think. To your cat, however, boxes are tempting for many reasons, and they're the perfect space to explore, sleep, and play in. But let's dive in deeper: Why do cats like boxes, exactly?

Read more
8 essential things you should be doing now to promote cat health
Keep track of these things to give your kitty a long life
A close-up of a peach and gray calico cat with amber eyes.

We believe sharing your home with any animal enriches life and makes you a happier, healthier person — and research agrees. But did you know that cats might actually be better for your health than dogs? According to a University of Minnesota study, owning a cat lowers your risk of suffering from a heart attack by an impressive 30 percent, likely more than that conferred by owning a dog, though results of research vary. (Don't worry, dog lovers. Research shows you're still happier and healthier than people who don't own any pets.) 

Considering how much your cat improves your health, it's only fair for you to keep a close eye on her well-being. We're here to help, so we've compiled a list of the most common forms of kitty illness and what you can do to promote cat health. 
#1: Monitor your cat's weight and activity level

Read more