7 Reasons Why Cats Become Aggressive
Even the most experienced cat caretakers can find themselves charged up on adrenalin when having to face a cat in the midst of a fit of aggression. But encountering a hissing, growling, screaming, and possibly even scratching and biting cat can strike terror into the hearts of people who don’t know how to handle a feline freakout. I suspect this is at least in part what happened in the tragic situation of Lux the cat, whose owners felt the need to barricade themselves in a bedroom and call 911 when Lux lost it after a series of traumatizing events. But cats don’t just suddenly go crazy: There are almost always warning signs and there’s almost always a good reason for cat aggression. Here are seven reasons why cats become aggressive and how to handle them.
1. Cats Become Aggressive Because They’re in Pain
Cats who are in pain will respond with hisses and swats when sensitive areas are touched. My cat, Siouxsie, does this if I accidentally put pressure on her sore hips. A hard yank on the tail, for example, can be quite painful. If the warning signs are ignored, a scratch and possibly even a bite may follow. This is especially true if the pain is a result of physical abuse such as being kicked or hit.
2. Fear Can Cause Cat Aggression
A cat that is terrified will respond with body language that’s obvious to an experienced cat caretaker: She will turn sideways and puff up her tail and fur in order to look larger. Her ears will flatten backwards, she will hiss and her pupils will be dilated. Attempting to approach a cat in this state is risking an aggressive reaction, not because the cat dislikes you but because she’s in the middle of a panic reaction.
3. Hormones May Cause a Cat to Become Aggressive
A cat who is not spayed or neutered is much more likely to be aggressive. Male cats in particular are biologically wired to fight with other male cats when females in heat are present. If you see two cats fighting, do not physically intervene because you will almost certainly become the target of the cats’ aggression.
4. Cats Can Get Aggressive Due to Frustration
“Redirected aggression” is the term for violent acts carried out by cats because they can’t reach the object of their predatory passion. For example, an indoor cat who sees another cat walking by or marking his territory in “his” turf may get into a highly reactive state. At that point, anyone unfortunate enough to be nearby, whether that’s another cat, a dog, or a person, may end up on the receiving end of the cat’s aggression.
5. Cat Aggression Happens Due to Stress
If a cat lives in a highly stressful environment — for example, a home in which people are fighting or a home with too many cats — it’s quite possible for that cat to be quick to respond aggressively. Like children who live in homes with a lot of verbal and physical violence, or a lot of unspoken anger, cats often act out the dynamics of their human families.
6. An Aggressive Cat Might Be Responding to Trauma
Don’t laugh: Cats can suffer from post-traumatic stress. Their brains are wired similarly to ours, and the effects of chronic anxiety from past human violence or struggling to survive on the streets can lead cats to become aggressive. In order to resolve this issue, a short course of anti-anxiety medication (prescribed by a vet, of course; don’t give your cat your antidepressants, please), homeopathic remedies or flower essences can help make a cat less reactive to triggers.
7. Chemical Imbalances Can Cause Cat Aggression
This is by far the rarest reason for cats to become aggressive. But like humans, some cats simply have biochemical imbalances that affect behavior. For these cats, antidepressants or anti-anxiety medications can be a lifesaver.
No matter what the cause of the aggression, there are almost always warning signs. If you understand feline body language, you’ll be able to see that your furry friend is getting wound up before the situation escalates to a crisis point. If you have a highly reactive cat and you want to help him or her, be aware that it will take time and patience — but take it from a person who has rehabilitated traumatized cats: The reward is so worth the effort!
How about you? Have you had an aggressive cat? Were you able to help your kitty feel better and become less reactive? What did you do to help her? Have you ever been unable to help an aggressive cat? Share your thoughts in the comments.
Read more about why cats become aggressive on Catster.com:
- All About Cat Hissing — Why Do Cats Hiss?
- Do You Have an Aggressive Cat — or Just a Brat?!
- Feline Non-Recognition Aggression: 4 Tips for Reintroducing Your Cats After One Returns From the Vet
About JaneA Kelley: Punk-rock cat mom, science nerd, animal shelter volunteer and all-around geek with a passion for bad puns, intelligent conversation, and role-play adventure games. She gratefully and gracefully accepts her status as chief cat slave for her family of feline bloggers, who have been writing their award-winning cat advice blog, Paws and Effect, since 2003.
20 comments on “7 Reasons Why Cats Become Aggressive”
My 2yr old ginger female fixates on birds (thru the window) in the eaves of my house. If I disturb her, not on purpose, she’ll ‘haw!!’ at me, hiss, and swipe at or try to bite me. I leave her be and come back later to make my bed-where this activity takes place. Perhaps she interprets my actions as trying to get HER birds.
This is for Brittany. For some reason, I can’t directly respond to your post. It sounds like she may have been expressing redirected aggression. Sometimes, things unbeknowstvto us, disturb a cat and the cat, will suddenly attack whoever or whatever is near by. My cat does this when she hears certain noises, for instance when I yell out if I stub my toe or hit my funny bone. She comes flying out of nowhere and bites me. Once she pierced my thigh with her teeth and I had 4 bite wounds. She used to attack another of my cats and bite her on the neck, but this other cat was so calm and tolerate, she never seemed bothered by the other cat {admittedly, it seemed like a Love bite] After this sweet cat died, we got a new older cat who does not tolerate the other cat and they get into some bad fights .
This happened over a month ago and was out of my control, but my family forced me to put down my non spayed 2 year old female cat after she attacked me 3 times. The first attack happened because my cousin jumped on me while I was sleeping, startling me, and my very anxious sleeping cat. She lashed out at us, jumped on us with her claws out and slashed us repeatedly. She was hissing and even spitting. Talk about a rude awakening!! Her spit was all over my pillows and headboard, not to mention my blood being all over my sheets. She cut me pretty deep in a couple spots on my legs, and I had a very deep cut on my wrist that I got from blocking my face. I tried to console her afterwards, and she began hissing at me and charging me… She was my first cat so my family was unsure of what to do. We called animal control and were forced to put her in hospital quarantine. After the quarantine, she seemed to be back to normal, so I brought her back home. The day after, I was crying in my room due to an unrelated issue. I guess it was my heavy/erratic breathing that set her off, but she attacked me again! In the same fashion as the last attack: Very aggressive, claws out, repeatedly slashing me. My legs got torn up pretty badly, and I was so terrified of her… We were able to trap her in a small cage we had, and she looked up at me wide-eyed and meowing as if nothing had happened. After that second attack, my family didn’t trust her and neither did I, honestly. They made me take her to get put down. I’m so torn up about this because I loved her so much, and she was so beautiful. I just have no idea why she turned on me so suddenly… Anyone have any idea? She’d always been on the edge and anxious, so I’m guessing maybe she had a hormonal imbalance. Thats what our vet told us, anyway… Someone give me some feedback please!
Hello. I have been incredibly worried about my cat for about a month now. We often refer to him as a “lover boy” because he’s most likely the sweetest cat you will ever meet. We named him Shadow because he follows me around like a dog (no, seriously, he follows me everywhere), he comes when you call him, he lets you pet him everywhere (even on his belly and paws!), he loves to snuggle, and he cries when he can’t see me (if I leave the room, if I close a door, etc). But for about a month now he’s been aggressive – but only under certain conditions. If I sit next to him on the floor with my legs crossed, he starts crying. His crying quickly turns into more of a warning; it gets higher, louder, and more threatening. He then proceeds to try to bite me anywhere he can: my arms, legs, even my sides. The bites never draw blood, however they do leave indentation marks that are quite alarming. It’s almost like he’s possessed. He tries to crawl into my lap (to get closer so he can bite me) and lightly scratches at my legs as he does so. He used to do it only in my room, but now he’ll do it in the living room when my parents aren’t looking. That’s another weird part about it: he only does it when we’re alone. He’ll immediately stop when my parents walk in my room. He only does this to me. Right now he’s sitting next to me and I’m petting him as if nothing happened five minutes ago. He does kind of bully our other cat, so maybe it’s redirected aggression because we often prevent him from bothering her? Please help.
My 3 year old female spayed cat has suddenly started being aggressive. My girlfriend of 3 years came over, wore a pair of moccasins that my cat had never seen before. The cat freaked out, ran into the bedroom. When we followed her, she poofed up, hissed and growled. She has never done this before. She repeated the behaviour today when I was putting on my socks. What the…??? She even swiped at me when I went to console her. Any ideas??
Hi Monty —
Sorry to hear that you’re having issues! We suggest talking to your vet or a behaviorist.
My female cat not spayed is loving and sweet and sleeps with me all the time. But anytime anyone comes over she will run up on them and then start hissing. She has swatted at others and after they leave she want to be loveable again but it is progressing to growling and hissing and lunging at me. Seems like anxiety as she does this to everyone but me. No one is hurting her and they try to sit still till she gets used to their smell but nothing works. She ends up hiding till everyone is gone but has started to do the same to me. I say it’s anxiety that she doesn’t know how to release but I have no idea how to help her calm down and not be anxious or too excited. Is this just possible since she has not been spayed?
My orange cat hates my guts half the time. Literally half the time. Some times I can hold him and pet him. Other times if I even try he attacks me. Like I’m bleeding right now cause if him being like this. There are also times he just starts peeing on me when I won’t let him go. I was trimming his nails and he tried yo get away and I wouldn’t let him go so he starts to growl and pee right in my lap. I go to pet him and sometimes he perks his head up to reach my hand, other times I get an inch from him and he hisses at me and runs away. I don’t know what to do. I’m tired of bleeding. I’ve taken him to the vet and described this issue to the vet and the vet said it’s normal. I need advice. There are no unfixed female cats around. He isn’t fixed but that’s my next move. Anything else I can do?
My 5year old male neutered cat has an occasioal aggression problem. He is usually very loving, sits in my lap and follows me around. He lets me kiss him and will turn his head up for me to do so. ( Sorry people, yes, I’m a cat kisser)! But, once in a while, he gets that look in his eye, stares at me intensly and then strikes out, biting me on the arm or leg. He does this so fast that you can’t really see him. He bites, releases and sits back as if to say, “there, I showed you”. He draws blood and leaves a tiny three cornered bite.
I wish I knew why he does this and what I can do about it. I also have an older female whom he sometimes chases. They tolerate each other, usually.
My 4 year old female cat does the same thing. She can be very affectionate towards me, and then out of nowhere she attacks me. It’s now happening more frequently, about every 2-3 weeks. If I’m sitting, perhaps looking at TV, I can catch her staring at me. If her eyes are dilated I throw a paper ball or something to distract her. If I don’t notice her, you can be sure that I will be attacked. My husband and daughter are shocked because I’m the one that feeds her and cuddles her. Her bites usually break the skin and sometimes the area swells and is sore. I don’t know what to do. I love my cat but I’m also fearful of her.
Neutered or not, male cats want to be the “Alpha” unless you have claimed the role. Nips/biting is one “I’M in charge” warning.
Like yours, my cat was loving, lap happy, and would do so without warning, but his most long lasting, frightening attack came when I tried to bring a cage-trapped feral into the home. After that, even if my cat saw me lingering with the feral outside for a few moments, I’be in danger of some nasty scratch/bites when I came in.
That “Dog-Whisperer” has many methods of claiming the Alpha role but none worked on my feline housemate.
I seemed to have 2 choices… Bring him to Animal Rescue or beat the crap out of him. His “Normal” attitude was so great that I was very reluctant to do the former, and too animal loving to do the latter.
After his 3rd, attack, I gave him a STRONG reminder of where his “suppers” came from. Mid-day I scooped up his dry food bowl ‘s contents and dumped them out, and did NOT put down his usual mid-day wet food “Supper.”by bedtime, he was already becoming super mellow and cuddly. Three words he recognizes are… “No” and Supper” and “Bad. ”
Combining the three words and… his name repeatedly, seemed to awaken a new awareness to him.
By morning, it was hard to ignore his plaintiff meowings, but I had promised myself to hold out for at least 24 hours.
About 26 hours in, I caved, and brought out his fav wet food, but held it out of reach somewhat as I quietly and calmly verbally reminded him of his badness. Any time after, if he even lightly bit, I’d walk over to the eating area while he watched and removed any food. Half a day was then enough. Mellowness ruled. ( For awhile.) BUT… Eventually he relinquished the Alpha title!
P.S. Any time I was outside to feed the feral, I took to putting indoor kitty into another room where he couldn’t watch, and if I had petted the outsider. I made sure to wash my hands of any feral scent on coming back in.
Could it be when your kitty stares at you, you are starring back with your eyes wide open?Try to slowly shut your eyes instead, a few times. Cats feel threatened when you stare at them with eyes wide open, better to have them slightly closed.
Catster, Catster, Catster, what are we going to do with you. You forgot one very important potential reason. She could be hungry. It is so sad and pathetic we humans dictate to these beautiful creatures when WE think THEY should eat, we dictate the times to THEM, and specifically, put the absolute horrifying stuff of nightmare legend crud garbage known and sold as commercial waste, I mean cat “food” in their faces, yet many wonder why they walk away, get agitated, don’t behave “properly”, get sick, and receive their untimely, wholly, and grossly hurrendous early euthanasia. AAFCO needs to get their head out their ass, step their game up, and look up to the standards set forth in Europe, where they have literally eliminated Feline Cancer, if they even give about quality control and allowable ingredients, they could take credit for reducing and removing kidney failure, hyperthyroidism, and all these other unthinkable diseases and early untimely deaths we are literally feeding my babies. But not me, I’m ahead of the curve. Omega 3 Icelandic wild caught fish oil, free range meats, quality dried, and water, water, water. Cats like to eat relatively frequently throughout the course of a single day. My 17 year old probably likes to have roughly 10 stomach fill ups in a day, in between her roughly 10 naps, and among her roughly 10 visits to either of her 2 running water fountains. I feed her real actual meat and protein frequently, NEVER E.V.E.R. complete crud garbage like Friskies, and almost never Fancy Feast, I go with Soulistic wet canned, Orijen dried, real catnip in the garden, ice in her water, and for being the oldest cat in the neighborhood, she’ll probably outlast them all too. My ideology, more food, more nutrients, more beneficial digestion, enzymes, greater immunity, more tools for her body to work with to fight disease and aging, and increasing her physical and cognitive ability. Doesn’t hurt she has two pet steps, and her own cozy getaway in the form of a tent on a couch. You may refer to me as The Egyptian. Thanks for reading.
So nice to hear someone so tuned into kitty. My boy is also on special diet, always has clean water. One cat and spoiled rotten, but does not get store food.
Your older cat, who had the surgery, maybe she is having pain still? If she is in pain she might feel vulnerable. I agree with the others who say get another vet! Then look into the pain issue.
Good luck, I hope your girls can be friends again.
I am having a hard time posting this for some reason.I think the aggressor feels very vulnerable.Seperate high perches might help.I have played with my seven all at the same time with a laser and they forgot about the aggression and even the shy one got involved,also rewarded them with treats.I agree about a new vet also.He may still be hurting.He needs reassurance and you should see if something else hurts.
just a shot here but maybe tuna oil on the non aggressor?keep them separated but initially offer some tuna to both within eyesight of each other.put tuna oil on the non aggressor often enough for the aggressive cat to smell it and associate the non aggressor with that scent.you don’t have to actually feed them some tuna every time you just want to make a pleasant association.Give the aggressor alot of space from the other cat.Sounds like he feels vulnerable.Maybe separate high perches.The aggressor needs alot of reassurance and patience.Even playing with them together can distract from the insecurity with a laser pointer or something that involves you all and then reward with treats.That helped us.Good luck.
Get yourself a new vet!!!
I have 2 spayed females, 6 & 7 who were best friends until the 7 yr old had surgery for bladder stones in April. She will attack my 6 yr old at every opportunity. The 6 yr old has ptsd! I have to keep them separated now. We tried pheromones & an antidepressant, but nothing helped. Now I have them eating in sight of each other separated by the babygate. Would love more info. My vet said to put her down but I can’t. Thanks
Run don’t walk to a different vet. Any professional who would say that cannot be trusted with your fur babies’ care. With that said, I feel your pain and hope your girls work it out.