Why Is My Cat Suddenly Aggressive?

If your normally sweet cat has started hissing, swatting, or biting, you’re probably wondering what’s changed—and if you should be worried.

At Hoof and Paw, we understand how concerning behavioral shifts can be, and we’re here to help.

Common Causes of Aggression in Cats

• Pain or illness – A sick or hurting cat may lash out

• Stress or fear – New pets, people, or changes at home

• Territorial behavior – Especially if another cat is nearby

• Redirected aggression – Seeing something upsetting and taking it out on someone else

• Hormones – Intact cats may be more prone to aggressive behavior

• Neurological issues or cognitive decline – Especially in senior cats

When to Call the Vet

If your cat:

• Starts acting out of character

• Shows aggression consistently or unpredictably

• Is unwell or in pain

• Has trouble eating, walking, or grooming

• Is acting confused or disoriented

We’ll rule out medical issues first, then help guide behavior changes with proven strategies and compassion.

Your cat’s behavior is a message. We’ll help you understand what it’s saying. If you’re feeling unsure or overwhelmed, we’re just an email away.

👉 MESSAGE US NOW

TL;DR:

Sudden aggression in cats is often a sign of stress or illness. Let’s find out what’s going on—together.