30 Subtle Signs Something's Wrong with Your Cat 

1 | Changes in their eating habits

While many cats are picky eaters to begin with, if your cat has a sudden change in his or her dietary habits, it's likely a sign something is amiss. According to Bales, if your cat suddenly decides to forgo their food, or scarfs down their meal in seconds, as though it's the only thing they've eaten in ages, that could be a sign they're not feeling well. While increased appetite can indicate a thyroid issue or diabetes, a sudden refusal of food can mean they're dealing with stomach issues, dental pain, or even more serious problems, like cancer. And to find out what really goes on behind the scenes when your pet's sick, check out these 15 Secrets Your Veterinarian Won't Tell You.

2 | Extreme fatigue

Cats are pretty sleepy as it is, and often snooze for up to 16 hours on the daily. However, if your cat is sleeping more than usual, or seems to be having a hard time waking up, it's worth it to take him or her to the vet. Fending off virtually any illness, from an upper respiratory infection to more serious conditions, can make your cat lethargic, so make sure you're keeping an eye on their sleeping habits.

3 | Excessive grooming

Cats are known for their meticulous grooming habits, but if your pet is suddenly grooming constantly, it's definitely a sign something is amiss. While stress is often the root cause of this behavior, it can also stem from parasites, allergies, or even neurological issues. And for more incentive to seek some feline companionship, discover these 20 Ways Cats Are Better Than Dogs.

4 | Dull fur

On the flip side, however, if your cat suddenly decides that their traditional grooming routine is no longer worth it, it's worth taking them in for a checkup. "Cats who are not feeling their best may decrease their grooming activity, so a dull, unkempt, or matted coat should prompt a further investigation," says North Carolina-based veterinarian Dr. Jananne O'Connell, of Banfield Pet Hospital. While a lack of grooming can indicate numerous conditions, from dental pain to depression, it can also be a sign of more serious health issues that could be life-threatening.

5 | Walking in circles

While it may be cute to watch your cat run around in circles, it could also be a sign that they're under the weather. Walking in circles could be an indication of an inner ear infection, vision issues, or neurological problems, among other potential causes, so if you're noticing this behavior, it's definitely time to call your vet.

6 | Increased thirst

If your cat is suddenly lapping up water like they've just run a marathon, don't wait to take them in for a check-up. Increased thirst can be an indication that your cat is suffering from diabetes, hypothyroidism, or kidney disease, none of which can wait for treatment.

7 | Hiding

Cats are notorious hiders, but so it may not initially seem troubling that they prefer a spot under your couch to their pet furniture. That said, when cats are ill with a variety of health issues, they'll often hide out more often than normal, so if your pet isn't coming out for meals, it's definitely time to call up your vet. And if you think cats are cold, well, just learn these 25 Hidden Ways Your Cat Shows Affection.

8 | Avoiding people

Even if your cat isn't necessarily hiding from you, avoiding you or guests in your home could be a sign that they're feeling under the weather. Various sources of physical pain can cause cats to retreat from human contact, as can invisible conditions, like anxiety.

9 | Different vocalizations

You may think your cat's meow is the sweetest sound in the world, but if your pet is suddenly yowling non-stop or there's a change in the pitch of their vocalizations, it's time to talk to the vet. "Cats communicate with humans through their vocalizations, and they can be more vocal or have different sounding meows if they aren't feeling well," says veterinarian Dr. Kelly Ryan, director of the Animal Medical Center of Mid-America.

10 | Sleeping less than usual

Your cat should be sleeping for about half to two-thirds of the day, but if they're suddenly spending the whole night awake, you might be dealing with a health issue that needs attention. Cats with physical conditions that cause them pain—as well as issues like anxiety or extreme hunger—can be reluctant to drift off when it's time to hit the hay.

11 | Weight loss

While it may be healthy for overweight cats to shed a few pounds, if your pet isn't on a specific diet and is losing weight, it's cause for concern. According to Dr. Amanda Landis-Hanna with PetSmart Charities, even a weight loss as small as half a pound can indicate that your cat needs medical attention.

12 | Hunching

We all develop some posture issues as we get older, but a hunch on your cat is definitely cause for concern. Hunching is often an indication of a digestive issue, or can stem from spinal problems, so time is of the essence when you start noticing this symptom.

13 | Eye changes

Is your cat tearing up over the years of devoted affection you've provided him or her? Probably not. "While we can easily recognize some signs of illness through a cat's eyes—like discharge, droopy eyes or the third eyelid covering part of the eye—dilated pupils, constricted pupils or one pupil that is dilated can be harder to notice but are still signs of illness," says Dr. Ryan.

14 | Gagging

If your normally hungry pet is suddenly gagging on its food, don't waste any time in getting them to the vet. While cats sometimes have increased difficulty consuming their food as they age, gagging can be a sign of everything from allergies to acid reflux, neither of which allow your pet to enjoy a decent quality of life if left untreated.

15 | Breathing through their mouth

While it may not be a big deal to see your dog breathing through its mouth, it may be a serious issue when your cat follows suit. While a cat breathing through their mouth can be a sign of an infection or allergies, Dr. Bales cautions that it may also be a sign of a life-threatening form of respiratory distress, and definitely merits an immediate call to the vet.

16 | Neediness

Though it may be nice to suddenly have your cat attached to your side, if that's a new behavior for your furry friend, it's time to get them checked out. If your cat seems to be constantly trying to get your attention, it could be a sign that they are attempting to indicate that they're in pain or need help.

17 | Flaky skin

A little cat dandruff could be caused by a bigger problem. Dandruff can not only be a sign of a dermatological condition or allergy, it can also be a sign that your cat is over-grooming, possibly due to stress.

18 | Difficulty jumping

While every pet gets a little creaky in their joints as they age, if your cat is suddenly having trouble jumping vertically, it's time to get them seen, according to Dr. Landis-Hanna. In addition to conditions like arthritis, a lack of vertical jumping may be the result of an inflammatory condition, injury, or, in extreme cases, a more serious issue, like cancer.

19 | A twitchy tail

A twitching cat tail is typically a sign of hunting behavior, but if your cat's tail never stops dancing, get your vet involved. While it can sometimes be a sign that your cat is peeved about something, a twitchy tail can also be a symptom of feline hyperesthesia, which can cause changes in their skin or bodily movements.

20 | Panting

A panting cat is not a happy camper. Panting can indicate that your cat is dealing with allergies, an upper respiratory infection, respiratory failure, or even a panic attack, among other potentially-serious issues.

21 | Weight gain

While your rotund cat may be adorable to you, sudden weight gain can also be a sign that something is seriously wrong. Weight gain can sometimes stem from fluid retention, hormonal issues, or even metabolic conditions, all of which should be checked out by a professional.

22 | Constant purring

While a cat's purr often indicates contentment, it can also be a sign that they're not in tip-top shape. Cats not only purr to communicate happiness, they also purr when they're sick or upset, so if their purr has changed, it's time to call your vet.

23 | A wet chin

Every cat occasionally dunks their little chin in their water dish, and it's virtually never a problem worth taking them to the doctor over. A constantly wet chin, on the other hand, can be an indication that your cat is drooling, which could be the result of them having trouble swallowing, a respiratory infection, dental health issues, fear, vomiting, or even cancer.

24 | Fur loss

That patchy fur on your cat generally isn't a good sign. Patchy fur can stem from conditions like anxiety, over-grooming, and allergies, meaning it's time to get your cat checked out if their coat is looking a little worse for wear.

25 | Sneezing

Much like humans, cats sneeze from time to time without greater medical issues at play. However, sneezing can also be an indication that your cat has an infection or allergies, so it's best to play it safe if your cat seems to be sneezing more frequently than normal.

26 | Looking suddenly older

According to Dr. Landis-Hanna, sometimes visual cues are enough to indicate that something is going wrong with your pet. If your cat suddenly looks older to you, it may be a combination of poor grooming habits and weight loss, both of which merit some veterinary care.

27 | Bad breath

While you'd be hard-pressed to find someone who describes their cat's meaty breath as sweet, per se, if your feline friend has a case of sudden-onset halitosis, it's time to get them to a vet. "Dental disease affects 85 percent of cats by the time they are 3 years old, which can cause bad breath, but dental disease can also lead to more serious issues like kidney, liver and heart problems," says Dr. Ryan.

28 | Avoiding the litter box

A change in litter box habits, even a slight one, may be an early sign that your cat is under the weather. "When a cat goes to the bathroom outside of its litter box, it could indicate a urinary tract infection, blockage, bladder stones, constipation, or kidney, liver or thyroid issues," says Dr. Ryan. Similarly, if your cat is using the litter box more or less frequently than usual, you should tell the vet.

29 | A lack of interest in their toys

If your normally playful cat suddenly has no interest in their toys, that may not be as normal as you think. Everything from physical pain to depression can cause your cat to have a lack of interest in the activities they once enjoyed.

30 | Dropping food

If your cat seems to drop more food than it actually gets in its mouth, you could be dealing with a medical issue. "Dental or oral pain from tooth lesions can cause unusual behavior when eating," says Dr. O'Connell. Similarly, older cats and those with more serious medical issues can develop muscle weakness that makes eating more difficult, too. And to find out what those mews and head-butts really mean, discover these 30 Surprising Ways Your Cat Communicates With You.

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