18 Signs That Your Cat Is Sick

Signs That Your Cat Is Sick

The Spruce / Ellen Lindner

It's important you be able to recognize the signs a cat is sick. It may be difficult to know if subtle changes in your cat indicate a health problem. Cats are experts at hiding illness. In the wild, this instinct can protect them from predators or other cats that might be a threat. Common signs that a cat is sick are vomiting, diarrhea, loss of appetite, lethargy, increased thirst, and many more. Learn the 18 most common symptoms for cats and what situations are an emergency.


How to Know If Your Cat Is Sick

Signs That Your Cat Is Sick

By the time you actually notice something is wrong with your cat, it might have been going on for a longer amount of time than you think. Note subtle changes in behavior and watch for more. Observe your cat's demeanor and body language. Does something seem off? Learn what is normal for cats and know what is normal for your cat. Never ignore obvious signs of illness. When in doubt, contact your vet for advice. 

  • Vomiting on occasion is not a concern. However, anything more than this warrants a trip to the veterinarian.
  • Loss of appetite can be normal for cats but it still should not be ignored. If your cat skips the occasional meal but otherwise eats normally, then you should watch closely for trends. If your cat stops eating entirely or is only eating tiny amounts, you need to get your veterinarian involved. Lack of eating for even a few days can lead to a serious problem called fatty liver or hepatic lipidosis.
  • Increased appetite may also be a concern, especially if it comes on suddenly in an older cat. Hyperthyroidism may be the explanation, but your vet will need to run tests to be sure. Increased appetite should not be ignored, even in younger cats. If nothing else, it can lead to overeating and obesity.
  • Diarrhea may indicate dietary indiscretion, intestinal parasites, and a variety of other problems. Left untreated, diarrhea can lead to dehydration and further intestinal inflammation. It's also very uncomfortable for your cat. Schedule a vet appointment and, if possible, bring a stool sample.
  • Weight changes in cats are always concerning, whether it's gain or loss. Either might be a sign of an underlying health problem. Weight loss is more urgent in the short term whereas weight gain is usually more harmful over time. If you are not sure about your cat's weight, make a vet appointment for a check-up or at least a weight check. 
  • Lethargy is a sign of a problem, even if it's subtle. Contact your vet if your cat seems to be lying around a lot, sleeping more than usual, or just generally has a low energy level. There is probably something going on with your cat's health.
  • Increased thirst can mean many things in cats. Most often it means there is a problem like kidney disease or diabetes mellitus. Many owners never even see their cats drink water. So, if you start noticing your cat near the water dish more than before, it means something. 
  • Changes in urination are always important to address. They often indicate a urinary tract issue or kidney problem. If you notice a change in frequency or quantity of urine, inappropriate urination, or blood in the urine, schedule a vet appointment. If your cat is straining to urinate and nothing is coming out, this might be an emergency, particularly in male cats. Bring your cat to a vet immediately.
  • Changes in breathing like wheezing, rapid breathing, shortness of breath, and raspy breathing should never be ignored.


If your cat is not breathing normally, it may be best to go to an emergency clinic. If the signs are very mild, see your regular veterinarian as soon as possible.

  • Discharge from eyes or nose indicates a possible upper respiratory infection. This can make your cat feel ill and stop eating. It may be contagious to other cats in your home. Your vet may recommend medications to help your cat recover faster.
  • Ear debris or discharge might mean your cat has an ear infection or even parasites like ear mites. Waiting to address this may cause the eardrum to become affected. Plus, it is very uncomfortable for your cat.
  • Skin irritation or hair loss may be a sign of allergies, external parasites, or another skin condition. It's also likely painful or itchy. Don't let your cat suffer needlessly. Your vet may be able to offer treatment options. 
  • Increased vocalization may mean your cat is sick, in pain, stressed, or just bored. It's important to rule out a health issue first before you explore the behavioral side of this issue.
  • Overgrooming may be behavioral, but it could also mean your cat has a skin issue or is in pain. If you notice overgrooming, start with a vet visit to try to get to the root of the problem.
  • Personality changes may be normal when they happen over time, especially as your cat ages. However, if your normally friendly cat is showing aggression, or your happy, confident cat is suddenly acting afraid, there is a need to further explore with your vet. If your cat seems confused or disoriented, then it's an even more urgent situation.
  • Limping and trouble jumping up are signs of an injury or a condition like arthritis. Don't assume your cat is not in pain because he is eating and acting normally otherwise. See your vet so the injury or condition can be treated appropriately.
  • Swelling in any area of the body should not be ignored. It may be a wound that has turned into an abscess. It could even be a tumor. Watch the swollen area closely. If it is painful, hot to the touch, or does not get better in a day or two, see your vet.
  • Bad breath is a sign of dental problems. Mild halitosis may not be urgent, but it means your cat's teeth should be checked soon. Severe bad breath should be addressed sooner. Also, watch for ​excessive drooling and bleeding from the mouth. If your cat has an oral infection, it exposes the whole body to the bacteria in the mouth. This could lead to problems with the heart and other organs.


There is another reason why cats and many other animals are less likely to show pain or illness: They simply do not have an emotional relationship with their discomfort. Animals tend to accept the pain or illness as the new normal and move on. It may not be until they are extremely ill that their sickness becomes obvious to humans.

Emergency Situations and Your Cat

Certain situations may be considered urgent. You shouldn't wait for an appointment at your vet when your cat is experiencing an emergency. Keep information about after-hours veterinarians handy in case you need to rush to one. If you see the signs of an emergency, do not delay. Go to the closest open veterinarian immediately:

  • Trauma (examples include falling from a height or being hit by a car)
  • Difficulty breathing
  • Gums that are blue, white, or very pale
  • Collapse, unconsciousness, or unresponsiveness
  • Seizure
  • Dizziness, imbalance, or circling
  • Inability to walk
  • Moderate to profuse bleeding 
  • Straining to urinate without producing urine
  • Exposure to a poisonous substance
  • Severe pain (showing signs like crying out loudly and excessively or acting aggressive when touched)
  • Body temperature over 104 or under 99 degrees Fahrenheit (normal is usually 100.5-102.5 degrees Fahrenheit)
  • Hasn't eaten properly in 24 hours

If you notice anything else your cat does that worries you, it's better to be safe than sorry. You can call your vet or the emergency vet if you need help deciding if something is an emergency.

How to Prevent Illness in Cats

Many owners underestimate the importance of routine veterinary care for cats. They may wait several years to bring their cats to the vet for check-ups. Worse, they sometimes wait until their cat is sick. It's understandable that people would want to avoid putting their cats through the stress of a veterinary visit. Some cats become very anxious or even aggressive at the vet. Rather than waiting, try to find a veterinary practice that is less stressful for your cat. Many feline-friendly practices are out there, some even cat-only practices.


If you don't want to go through the stress of getting your cat into a carrier and taking it to the vet, you may consider finding a mobile vet who can come to your home. Many cats do better in a familiar environment.

Annual veterinary exams are essential for cats. Senior cats can benefit from biannual check-ups and routine lab work. These visits give the vet an opportunity to examine your cat when he appears healthy. The vet may find minor abnormalities on the exam that indicate a minor problem before your cat gets really sick. Early detection might mean you and your vet can take action before the illness becomes serious.

You can also keep your cat as healthy as possible by feeding a healthy diet. A healthy diet can help your cat avoid obesity and a wide array of other health issues. Many vets recommend wet diets high in protein and low in carbohydrates.

Be sure to use routine parasite prevention as recommended by your vet. This can prevent fleas, intestinal parasites, and other parasites from making your cat sick.

Provide a happy, low-stress home for your cat. Keep fresh water available at all times and plenty of clean, accessible litter boxes in your home. In smaller homes or multiple-cat homes, provide vertical space like cat trees and wall shelves.

  • Can my cat's sleeping positions tell me if they're sick?

    While many positions that cats sleep in can indicate pain, the most serious is if they're sleeping with their hind legs and back arched, and their paws beneath their body. This position may indicate your cat needs medical attention. Please call your vet!

  • What do I feed a sick cat that won't eat?

    If your cat's not eating, you need to call your vet before you think about tricks to get it to eat! Once it's squared away that your cat is okay it's time to load it up with certain foods that either act like appetite stimulants (liver and tuna, for example), or a high-calorie supplement.

  • How do I comfort a sick cat?

    Cats are solitary, and more so when they are under the weather. While hugging your ailing cat might make you feel better, it's likely not what your kitty wants. The best way to comfort your sick cat is to provide it a warm and quiet place to sleep, make sure it has easy access to its box and food—perhaps you can move them closer?—and let it rest.

If you suspect your pet is sick, call your vet immediately. For health-related questions, always consult your veterinarian, as they have examined your pet, know the pet's health history, and can make the best recommendations for your pet.
Article Sources
The Spruce Pets uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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