Cats suddenly change their temperament, becoming pouncing and biting, which confuses and even injures many cat owners. This situation does not happen without reason; usually, cats convey information through behavioral changes. Understanding these signals is crucial to improving the human-cat relationship.

The possible reasons for cats' sudden aggressive behavior can mainly be summarized as follows:

• Physical discomfort or pain: This is one of the most common reasons for cats suddenly changing temperament and showing aggressive behavior. Just like people get cranky when sick, cats may show aggression when feeling pain or discomfort to avoid being touched at painful areas. Potential health issues include arthritis, dental diseases, injuries, infections, hyperthyroidism, epilepsy, or neurological problems, all of which may cause a sudden temperament change. Especially if a usually gentle cat suddenly starts attacking people, health issues should be considered first.
• Fear or anxiety: When cats feel scared, nervous, or lack a sense of security, they may attack to protect themselves. This is a defense mechanism. Sudden loud noises, unfamiliar environments, new family members (including new pets or people), or even daily environment changes (such as moving, rearranging furniture, or strangers coming to the house) may cause cats stress and anxiety, triggering aggressive behavior. Cats lacking early socialization are also more prone to fear-induced aggression.
• Play aggression: Especially during kittenhood, cats learn hunting skills and social boundaries through play. If a cat lacks opportunities to play with its own kind during growth, or if owners often tease them with hands or feet, cats may fail to understand boundaries and mistake human hands or feet for prey, exhibiting pouncing, biting, and scratching during play. This behavior may continue into adulthood.
• Redirected aggression: In this case, cats may get excited or angry after seeing or hearing a stimulus they cannot directly reach (such as another cat outside the window or a bird). Unable to react to the source, they redirect their aggressive impulse onto a nearby object, for example, the owner nearby or other pets. This type of aggression usually happens suddenly with high intensity, sometimes leaving people baffled, feeling like “taking the blame” unfairly.
• Petting-induced aggression: Some cats may suddenly bite or scratch when petted on certain spots (such as the belly or base of the tail) or after prolonged petting due to overstimulation or discomfort. This usually signals “enough, please stop.” If owners fail to notice these signals (e.g., ears flattening back, rapid tail flicking, skin twitching), cats may escalate their actions.
• Territorial behavior: Cats have strong territorial instincts, and when they feel their territory is threatened, they may show aggression towards “intruders” (including other animals or people) to defend their territory.
• Attention-seeking: Sometimes cats adopt extreme behaviors, including mild biting or scratching, to get the owner’s attention. If this behavior previously succeeded in gaining attention (even negative), cats may remember and repeat it.
• Hormonal influences: Unneutered cats, especially during heat cycles, may become emotionally unstable and more aggressive due to hormonal fluctuations.

How to respond to sudden aggressive behavior in cats?

When cats suddenly become aggressive, remember not to punish or shout loudly, as this may increase the cat’s fear and anxiety, causing the opposite effect. It is important to stay calm and try to understand the reasons behind the cat’s behavior.

1. Rule out health problems: Any sudden aggressive behavior, especially without an obvious trigger, should first prompt a visit to the vet. The vet will perform a thorough physical examination to exclude potential diseases or pain issues. This is the primary step to solving the problem.
2. Observe and record: Carefully observe the time, location, target, and context before and after the aggressive behavior. Does the cat show signs such as flattened ears, dilated pupils, hissing, growling, or rapid tail movement? This information can help you, the vet, or a professional animal behaviorist analyze the type and cause of aggression.
3. Avoid triggers: If you can identify triggers (such as petting certain spots, specific sounds, or scenarios), try to avoid these situations.
4. Provide a safe space: Give your cat a quiet, hidden, and secure place, like a cat bed or a high cat tower, where it can hide when feeling stressed or scared.
5. Increase environmental enrichment: Ensure your cat’s living environment meets its natural needs by providing sufficient toys, scratching posts, and climbing structures, allowing cats to scratch, bite, climb, and explore, releasing energy and reducing boredom and anxiety.
6. Use toys for interaction: Always use interactive toys such as wand toys or laser pointers to play with your cat, avoiding direct hand or foot play that may reinforce play aggression.
7. Gradually build trust: For cats aggressive due to fear or lack of socialization, patience and time are needed to build trust. Gentle interaction and offering treats can help the cat gradually relax.
8. Consider pheromone products: Some pheromone products can help relieve cat stress and anxiety and can be tried under veterinary guidance.
9. Seek professional help: If aggressive behavior is severe or does not improve, it’s strongly recommended to consult a vet behaviorist or certified cat behavior consultant. They can devise personalized behavior modification plans based on the cat’s specific situation.

Frequently Asked Questions

• Is a cat suddenly biting a dangerous signal? Yes, if a usually gentle cat suddenly bites or scratches, it may indicate pain, severe fear, or stress and should be taken seriously with professional help promptly sought.
• What should I do if bitten by a cat? Cat bites and scratches can transmit bacteria causing infection and potentially rabies (if the cat is not vaccinated). If bitten or scratched, immediately wash the wound thoroughly with soap and water and seek medical attention, especially if the wound is deep or shows signs of infection like redness or pain. Additionally, ensure the cat’s rabies vaccination status is confirmed.
• Can a cat’s aggressive behavior be completely corrected? With scientific methods and patience, many cats’ aggressive behaviors can be improved or controlled. However, in cases related to underlying diseases, genetics, or early trauma, complete elimination may not be possible but frequency and intensity can be reduced through management and adjustment.

In summary, a cat suddenly changing temperament and exhibiting aggression is its way of “speaking.” As responsible owners, we need to listen patiently, find the reasons behind the behavior, and take appropriate measures to help the cat regain inner peace and security. This is not only for our own safety but also for the cat’s physical and mental health and well-being.