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Why Is My Cat Suddenly Acting Out

Learn why cats may suddenly start engaging in bad behavior.

Is your cat suddenly engaging in bad behavior, reminding you of a child acting out? Does it have you at your wits' end, wondering why your sweet kitty suddenly seems out to get you?

Reasons Cats Start Unwanted Behaviors

The number one thing to consider when your cat suddenly starts acting differently is that there may be a medical problem. Here are some examples:

If your cat begins a new, unwanted behavior, make a vet appointment first, even if it doesn't seem like an issue that could be medical.

If the new unwanted behavior your cat is engaging in is aggression, visit the vet and check here for more information: "Cat Aggression Overview."


After a medical condition is ruled out, the next most common reason cats engage in unwanted behaviors is stress. Things can cause stress in cats that humans may not understand, like:

  • A change in an owner's schedule.
  • A new pet or person in the home.
  • The loss of a pet or person in the home.
  • Not enough interactive playtime with a human.
  • A dirty litter box.
  • Change in furniture positioning or remodeling of the home.
  • Loud noises.
  • Not being able to get to the food bowl because of housemates blocking them.

Consider all the things that could be causing your cat stress and eliminate them one by one to see if the behavior changes.

The third reason cats begin unwanted behaviors is that they are bored. Indoor cats don't always get enough stimulation or exercise, and owners need to make sure they're doing everything they can to provide those things. Be sure you're engaging in daily interactive play sessions where you simulate prey behavior for your cat to exercise his hunter instincts. Here are some other ideas for providing stimulation for an indoor cat:

  • Get an automatic cat toy that turns on at intervals while you're gone during the day.
  • Teach your kitty to walk on a leash and go outside routinely.
  • Set up a bird-watching station by placing a cat tree near a window with a bird feeder outside.
  • Make your cat "hunt" for food by hiding kibble in small amounts around the home every day.

You May Also Like These Articles:

Hyperthyroidism in Cats

Cat Not Using Litter Box? Inappropriate Urination in Cats

Stress in Cats

Feline Lower Urinary Tract Disease

Interactive Playing with Wand Toys

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