Why is my cat suddenly aggressive and biting? Anxiety or illness?

Thank you for contacting Petco Pet Education Center, formerly Petcoach with your question about Brett. She is a beautiful girl! I'm wondering if the move has caused this change in behavior. Moving is very stressful for a cat, and that can lead to aggression. I'd try using Feliway diffusers around the home. These release calming pheromones that can help relax her. I'd pair that with a Sentry calming collar. This will release calming pheromones when in contact with her skin. If this doesn't help, then I'd have her seen by a vet for a health check. I hope this helps!

I'd recommend stopping any attention as soon as Lizzie starts to exhibit any biting or pre-biting behavior (like rubbing against your hand). Immediately stand up and walk away if any aggressive play or biting occurs. Withdrawal of social contact with be a powerful learning tool for Lizzie. Also get plenty of new toys and rotate their use so Lizzie has appropriate things to play with and does not get bored. A Feliway Diffuser may be used to help reduce biting behavior and anxiety for Lizzie. Thanks for using Petco Pet Education Center, formerly Petcoach and good luck!

There could be a reason for Aspyn's change in behavior. Sometimes a sudden change behavior can be a sign of a medical illness. I think it would be a good idea to have her seen by a vet for a health check.

Cats can bite when they are feeling stressed, ill, or in pain. If Mason's behavior started suddenly it is best to schedule a veterinary exam to make sure there isn't an injury or illness causing him to act out aggressively. If he checks out healthy, then looking for causes of stress such as petting him when he wants to be alone, new people or pets in the house, or even limited access to resources. Making sure Mason has a place to hide and rest away from traffic and noise, access to his own food, water, and litter can all help reduce stress. Pheromone diffusers in shared rooms may also help decrease stress. Finally, playing with a toy, or only petting him when he approaches you may help Mason feel more comfortable with you and reduce biting incidences.

It's possible Mica is feeling a little stressed, or is a bit under socialized. If the behavior happened suddenly or occurred after a surgery it is also a good idea to schedule a vet visit as behavior changes can sometimes indicate pain or illness. if Mica checks out healthy, you may need to practice some socialization skills. This includes making sure she has a place to hide/relax when people are over. if she does check out new people, have them toss a treat or play with a favorite toy such as a feather on a stick that can introduce positive interactions rather than attempting to chase or pet her. If there are other pets in the house causing stress, making sure she has access to food, water, litter and bedding without competing with other pets can also help to reduce stress. Pheromone diffusers in plug-in or collar form can also release a calming pheromone which can help with stress and anxiety. If the behavior continues it is also a good idea to talk with your vet or a veterinary behaviorist about a training plan that may include medication to help reduce anxiety while instilling calming behaviors.

If this is a recent change in behavior I'd recommend having your veterinarian perform a thorough physical examination as a first step. Some common diseases in older cats like hyperthyroidism can make them much grumpier than usual. Pain from arthritis can also make cats react in an aggressive way. If your veterinarian feels there is no medical reason for the behavior change I would then recommend talking to a feline behavior specialist to see if there are changes you can make at home to address this behavior. Cat bites are no joke - veterinarians have lost fingers due to infected cat bites and cellulitis! But it sounds like there could be some other things to look into before deciding on euthanasia.

It could have been redirected aggression or you may have inadvertently caused her discomfort when you picked her up. Consider a pheromone product, such as Feliway Friends or MultiCat, to decrease any anxiety or aggression in the home. Seek medical al attention for yourself.