How to Solve Aggression in Household Cats

Aggressive house cats
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Are your cats having trouble getting along? It's possible that sometimes good feline buddies in the past can change their minds about each other. One minute, two cats will be engaged in mutual grooming, and the next, they are locked in a tooth-and-claw battle.

Aggression can be scary to witness and downright dangerous for your cats. You can restore calm to your home by learning how to identify what type of aggression your cats are displaying and employing techniques to stop it.

illustration of ways to break up cat fights
Illustration: Kelly Leigh Miller. © The Spruce, 2018

Why Do Household Cats Get Aggressive?

Aggression between housemate cats can come in several forms with different causes. It may be a playful exchange, sexual tension, a territory dispute, displaced anger, or just a simple female "catfight." If you can determine the type or cause of aggression, you have a better chance of solving the issue with an appropriate technique.

Play Aggression

Also called "play fighting," play aggression starts at an early age with littermates, or with non-related kittens sharing a household. Cats have a natural instinct for survival, whether in the wild or in a cushy home, and early-on are taught predator-prey behavior by their mothers. One kitten will "stalk" the other, then pounce its unsuspecting prey, and the fun is on. Kittens will trade off roles with the victim chasing its former predator. The "chase me" game is often a favorite in multi-cat homes among cats of all ages. 

Play aggression is also a natural (and normal) step toward establishing a permanent hierarchy or "pecking order" among feline housemates.

Play fighting is usually harmless fun. Intervention is only necessary if it appears that a cat is being hurt, if the fighting continues for too long, or if it turns into sexual aggression. To protect your cats against scratching injuries, trim the cats' claws regularly, which is generally a good practice for regular kitty maintenance.

Sexual Aggression

Even neutered cats occasionally partake in sexual aggression, especially if they were neutered after sexual maturity. In some cases, cats' sexual aggression toward each other borders on what is called dominance aggression or territorial aggression.

Sexual aggression is easy to identify. The aggressor will bite the nape of the neck of the victim cat and attempt to mount it using thrusting hip movements used in mating.

Sexual aggression between cats can be discouraged by scruffing. This is a close approximation of the actions a mother cat will take with an unruly kitten. Scruffing is done by grasping the loose skin at the scruff of the neck of the aggressor cat, then gently, but firmly, pushing him down toward the floor.

You can accompany scruffing with loud hissing to reinforce a cat's memory of its mother from kittenhood. The aggressor cat will likely relax into a subservient posture and may even roll over slightly. You may also be able to stop sexual aggression by redirecting your cat to another activity such as playing or eating.

Territorial Aggression

Territorial or dominance aggression can sometimes arise suddenly between two relatively evenly-matched cats. It may take place between males, females, or one of each sex. Territorial aggression is the form of fighting that is often accompanied by marking with urine. If you notice urine spraying during a fight, then it is clearly a territorial dispute.

The aggressor cat may not necessarily be an older cat, nor the one that has been in the household the longest. The aggressor will preface its attack with posturings such as a raised back, laid-back ears, and growling and hissing. The aggressor will then likely try to leap on its victim and attempt to bite the back of the neck. In many cases, the "victim" cat may back down, turn, and walk slowly away. This is a sign that a social hierarchy power struggle has begun.

Other times, the victim will give tit for tat, and a violent battle may ensue. Do not attempt to physically separate two fighting cats. In the heat of the fight, they will not recognize you and severe injury could result. Use a water pistol or throw a large pillow at the fighting cats to distract them from the fight, and then, physically separate them in different rooms.

Most housemate cats will eventually resolve their disputes. One will reign as the alpha cat, and the other will be satisfied with its lesser role in the hierarchy. There are some cases where you may be faced with the dilemma of two cats who will never get along and may need to be permanently separated. But, before that, you can seek the help of a cat behavioralist or your veterinarian to come up with more advanced solutions.

Displaced Aggression

Displaced aggression has to do with a trigger that bothers the cat, and then the feline takes its aggression out on another cat (or human). This is also known as redirected aggression.

The best way to deal with it is to remove the cat's stressor. If you notice that there is something bothering one cat, and this leads it to launch an attack at another non-antagonistic cat just sitting idly by, manage the scene. For example, if the cat was agitated when it saw a neighborhood cat walk by outside the window, you can draw the blinds.

Redirected aggression is usually a temporary situation unless you allow it to escalate. If the two cats usually get along, you can reset the relationship by keeping the two cats separated for a day or two until they both forget the incident.

Female Cat Fights

Female cats have their own playbook and are prone to cat fights. They are often very territorial and resent other females intruding into their space. Female-on-female aggression most often takes on the characteristics of territorial aggression, and you handle it much the same way.

Another form of aggression unique to female cats is that of aggression toward an adolescent male kitten whom they may have "adopted" and cared for when it was younger. One day (much to the young cat's surprise and dismay) his previously loving surrogate mother suddenly turns on him, growling, hissing, and attacking. This form of aggression may take place whether or not the female is spayed, or whether or not she has born kittens herself. It may be described as a "get out of the nest" aggression.

This kind of behavior is also observed in big cats. It is not unusual for a pride of lions to chase off the adolescent males, forcing them to move on elsewhere to establish their own pride.

How to Stop Cat Aggression

Just as there are many forms of cat-to-cat aggression, there are several ways to settle aggressive disputes by distraction, physical intervention, and medical treatment. Intervene when necessary and provide regular exercise with interactive toys. Do this and your cats are likely to enjoy peaceful companionship for years.


Overly zealous play aggression, sexual aggression, and most territorial and dominance aggression can be dealt with effectively by distracting the cats and redirecting their attention. You can also throw a pillow at the fighting cats, spray them with water, or try to distract them with food. If that doesn't work, try these other distractions:

  • Loud sounds: Clap your hands, then say "No!" or "Time Out!" in a loud voice. Or, blow a whistle or sound an air horn or another loud instrument.
  • Hiss: This sound is an imitation of their mother cat and is a lesson a cat remembers well into adulthood. It can work effectively along with scruffing.
  • Give the cat a toy: Provide the aggressor cat with a large stuffed toy such as a teddy bear. Keep it aside as its own personal "surrogate victim," and throw it to the cat to redirect their attention away from the actual feline victim. You can also bring out an interactive toy, such as Da Bird, to redirect all its pent-up aggressive energy.

Physically Separate Them

Never physically intervene between two cats locked in combat. If you find a moment (during pauses between attacks with less violent fighting or during sexual aggression) where you can grab the aggressor by the scruff of the neck, this is extremely effective. Use a distraction method prior to scruffing the aggressor.

Usually, the victim cat will flee the scene as soon as the other cat is distracted. Once you are sure the aggressor has calmed down, release the cat and talk to it quietly. Give the cat a few gentle strokes, much like how a mother cat would lick and groom the kitten she has just disciplined.

Another form of physical intervention is segregation. This may be necessary when several fights have occurred between two cats or in the case of redirected aggression. Assign a "time out" room for the aggressor cat, and allow the victim to have the rest of the house. This type of separation can take place in as short as an hour or two or as long as a day or two. Some cats might even need several months, but most will eventually develop their own peace accord.

Medical Treatment

If all else fails, you may have to resort to medication for the aggressor cat or the victim. Be sure to talk to your veterinarian or a specialist in cat behavioral problems about your concerns. It is important to rule out a medical problem with one or both cats before moving on to treatments. There are a few medical therapies to explore:

  • Prescription medications: Fluoxetine, alprazolam, trazodone, and other anti-depressant and anti-anxiety medications may be recommended for one or both cats. Some are prescribed for the aggressor cat to calm down their aggressive tendencies.
  • Nutraceuticals/supplements: Calming agents in the form of treats may be helpful to minimize stress and anxiety in one or both cats. A common form recommended by many vets is Solliquin, which helps balance behavior and encourages relaxation.
  • Holistic remedies and other natural remedies for stress like essential oils or herbal treatments are available for stress or fear that accompanies aggression by another cat.