Recognizing the Signs of Illness in Cats

by Cat Behaviorist Rita Reimers

Updated for 2026

Does My Cat Need to See the Vet?

Is my cat sick? It’s a question I’m often asked by clients and friends alike is, how do I know if my cat needs to see a veterinarian?

My answer is usually simple: if you’re asking yourself that question, it may be time to make an appointment.

Cats are masters of disguise. Because cats evolved as both predators and prey, they often hide signs of pain, illness, or injury. Even though your beloved feline is domesticated, those survival instincts have not disappeared.

Signs Your Cat May Be Sick

Because cats often hide illness, subtle changes in behavior are sometimes the first sign something is wrong. Watch for changes like these:

• sleeping more than usual
• personality changes
• more vocal than normal
• drinking more water than usual
• eating less or skipping meals
• seeming unlike themselves
• hiding more than usual

When Pinky began sleeping more than usual and seemed less like herself, I knew something had changed.

Trust Your Instincts

If you’re asking yourself, “Is my cat sick?” trust your instincts. Even if none of these changes are obvious, you may still feel that something isn’t right. If your instincts are telling you there may be a problem, call your veterinarian. With Pinky, my instincts told me something was off before the signs were obvious.

Avoid relying on Facebook friends, relatives, pet sitters, or groomers to make medical judgments about your cat. While they may care and want to help, they are not a substitute for veterinary advice.

No one knows your cat better than you do. You know their normal habits, routines, personality, and behavior better than anyone else.

When in Doubt, Call the Vet

Thankfully, Pinky bounced back to her usual self after getting the care she needed. Sometimes a vet visit ends with the happy news that nothing serious is wrong, and that peace of mind is valuable too.

Cats often hide illness until a problem becomes more advanced. Acting early can protect your cat’s health and, in some cases, save their life. Recognize the signs of illness in your cat, and be prepared to go to the vet when in doubt.