Cat suddenly aggressive? 9 things you can do when kitty goes Jekyll and Hyde

Cat suddenly aggressive? 9 things you can do when kitty goes Jekyll and Hyde

When good pets break bad: unprovoked aggression in cats

cat suddenly aggressive
I said it’s MINE!

Unprovoked aggression in cats can be a shock to a cat owner. A cat may suddenly bite you while you’re petting him, or turn on the other cats or pets in a household. She may swat, hiss, and growl. Perhaps she stares you down with big, gleaming eyes that threaten to melt you into the floor.

Cats can suddenly become aggressive for a variety of reasons. Here are 9 common reasons for unprovoked cat aggression and 9 things you can do about it.

Health-issue aggression: The first thing to do if your cat is suddenly aggressive is to make an appointment with a vet. Be sure the cat is in a carrier. Your newly angry cat may not want to get in, though. One way to pick up an aggressive cat is to go up behind it, hold the cat between your legs, and wrap it in a towel like a kitty burrito. Then gently place the into the carrier, letting the towel fall to the bottom of the carrier.

The vet may find that your cat is in pain. They may do a physical exam and find injuries. An X-ray may detect arthritis. The cause could also be illnesses and infections. Pain and discomfort can make humans angry, and cats are no different. Aggression is just extreme defensiveness. Declawing is a cause of aggression in cats, according to a study written about in ScienceDaily. It can lead to lasting pain and injuries in the cat. The cat may need pain management, which could calm its aggressive behavior.

Ask for a test for Lyme and other tick-borne diseases such as babesiosis. These common illnesses have been known to cause aggression in dogs and humans, and cause pain and discomfort. Lyme exists in all 50 states. Even indoor cats have some chance of getting a tick bite, since ticks can come in via outdoor pets or mice.

Your vet will come up with a reason for the sudden aggression and offer a treatment plan. It may include medications and behavior modification. If your angry cat just doesn’t want to take its meds, you can try the technique of standing behind the cat and holding the cat between your legs until you can get the cat to swallow the pill or liquid. Be sure to stroke the cat’s throat to get it to swallow.

Petting-based aggression: If your cat is not normally aggressive, but becomes ferocious when you’re petting her, be sure to pay close attention to her mood swings. Cats can suddenly get triggered. Maybe you’ve touched a sensitive area (if you suspect that’s the case, take her to a vet) or the petting is overstimulating her. Cats can be wired in a high-strung way.

If you see your cat’s tail twitch, her eyes look at your hand, or her ears flatten, pull your hand away. You can try giving a treat or other distraction to veer off the attack. Don’t make eye contact, as this can trigger aggressive behavior. But overall, it may be best to limit petting time. Just let her be.

Be sure nothing external is bothering your cat. Talk to her softly and don’t touch her unless she’s clearly in the mood.

Territorial aggression: If your cat is suddenly a hellfire when a new pet is introduced, think of it this way: what you think is his new best bud is an invader on his turf. He might be attacking or hissing out of fear. He will have to be sure that this new roommate is harmless.

Sometimes cats are suddenly aggressive toward their owner. They may not let you walk by without a swipe, or stare at you with a terrifying glare. They may see you as another cat who needs to be dominated. Don’t try to dominate back.

Maternal aggression: If your cat has kittens, then her Mama Grizzly will come out when any perceived threat to her precious brood comes near.

Inter-cat aggression: In a multicat household there can be issues of status and dominance.  All cats should be spayed or neutered, as sex hormones trigger dominance behavior in both male and, less commonly, female, toward male cats. If your cat is fighting with other cats or pets, keep them physically separated.

A tiff often starts with staring. If you can step in and block the cats from seeing each other, that can head off the rumble. Use cardboard, baby gates, plastic, or any other convenient barrier that blocks their view and keeps them apart. Don’t put yourself between two “mad catters.” If you see them about to attack,  you can make a loud noise to distract them.

If a cat gets aggressive toward another cat, dog, or other pet, you may need to start all over and slowly reintroduce them to end the feud.

Redirected aggression: A cat may be in predator mode from some external stimulus, such as a bunny outside the window or something indoors that’s frightening to them. They may transfer their fear onto you. You may just be in the wrong place at the wrong time. Try to figure out what’s bothering them. If there’s a new odor or even a piece of furniture that scares them, remove it. Let your cat rest in a quiet place without a lot of bright light.

Play aggression: Similarly, your cat may be in “play” mode and swat at you as if you were a mouse to be batted around.

Fear-based aggression: Cats can have PTSD. If you have a rescue cat or one who has been through trauma, they can have flashbacks that suddenly make them aggressive. For instance, putting them into a cat carrier could cause a panic attack. Or they may interpret simple attempts to play with them as an aggressive move on your part. Don’t try to get them to do things they don’t want to do.

Catnip aggression (not a formal term):  I don’t think this is common, but it happens. Some cats freak out from even a small exposure to catnip. They may even attack. It may be more common in cats who were rescued or have had other trauma. Obviously, if this happens, remove the catnip and keep it away forever. Your cat will go back to normal after having some quiet time.

How to calm an aggressive cat

Treats: Treats are great method of discouraging this type of behavior. You can try to ward off aggression with treats and other distractions such as toys or pointers. Reward your cat with positive reinforcement.

Aromatherapy: try a calming collar from a pet store. It smells like lavender and has cat pheromones that have a relaxing affect.

Medications: yes, there is such as thing as kitty Prozac and other drugs. This should be a last resort, but it can helps cats who are aggressive or neurotic and do things like tear their fur out. If the cat is in pain, it may need pain treatment and a remedy for the cause of the pain.

Rescue Remedy or Valerian: A drop of Bach Rescue Remedy can really calm your cat (and you! though you will need a bit more of it). It has helped with fearful cats. Be sure to consult your trusted vet about things like Rescue Remedy and other herbs such as valerian.

Time out: Turn down the lights and let the cat be alone in a place she feels safe and comfy and that’s near her food, water, litter box, toys, and treats. She may just need to chill.

A hiding place: if your cat can’t have a whole room to herself, give her a nice box with a pillow where she won’t be bothered. (“I vant to be alone!”)

Spay and neuter. Sex hormones get the best of us and your cat is no different, in fact, cats in heat or cats sniffing other cats’ hormones can be very aggressive.

Lots of play: a cat tired from playing will have less energy to be aggressive with.

A space of their own: if your cats aren’t getting along, keep them apart with their own food and water, litter box, and play areas.

Consult a cat behavior expert: I’ve done this and it wasn’t that expensive; it was a half-hour phone consultation. Ask your vet for a recommendation or check out this article for more info.


Keep a journal of when your cat suddenly becomes aggressive

Write down all triggers, times, and dates of sudden aggression in your cat. Track changes to the cat’s moods, changes to the environment, your cat’s diet, introduction and behavior of people or other animals, sights, sounds, and smells, new objects, any new stimuli. Also keep track of things that were in your home but no longer there. Write down interactions, dates, and times of the day. Cats hate change. Even the smell of a new carpet might be scaring your cat. You can use an online calendar for this if you want.

Never punish a cat for aggression, even mildly; that will only make them more aggressive. Don’t use spray bottles or things you think “aren’t that bad.” Your cat can tell if you don’t like what they’re doing. But they’re not being aggressive to get at you, they’re acting that way because they can’t help it. Something is scaring or challenging them.

Remember, aggression is normal and healthy in certain situations and you should only try to “do” something about it if it’s out of control. You can’t necessarily keep a cat from biting you when you pet her, other than try to anticipate it so you pull your hand away–and keep a first-aid kit around. I’m not trying to be hopeless, just realistic. In the majority of cases, understanding goes a long way in solving the problem.

Some resources:


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