Changes in Behavior
One of the most common signs that a cat is unwell is a change in their normal behavior.[1] Healthy cats are usually active and energetic, but a sick cat will often become lethargic and sleep more. According to a 2020 study, over 50% of cat owners reported increased sleeping and inactivity as a sign of illness in older cats.[2] Additionally, a sick cat may isolate themselves and hide away in closets or under furniture rather than seek out human companionship.[3]
Other behavioral changes to look out for include decreased grooming, so their coat appears messy or unkempt. A sick cat may also show a complete loss of interest in food or play. Cats who are normally social and affectionate but become irritable, aggressive, or withdrawn when ill require immediate veterinary attention, as these anti-social behaviors can indicate severe pain or distress.[1]
In general, any unexplained significant behavior changes in your cat, especially lethargy, appetite loss, and hiding should prompt a veterinary visit to discover the underlying cause.
Changes in Eating Habits
One of the most common signs that a cat is unwell is a change in their eating habits. Cats who are sick may eat less or more than usual, become fussy about what they eat, or experience weight loss or gain [1].
A decreased appetite or picky eating can indicate illness, stress, metabolic disorders, infections, dental problems, nausea, or pain [2]. Cats who feel unwell tend to eat less, which can lead to weight loss. Senior cats are especially prone to eating less due to illness or medication side effects.
On the other hand, some cats with illnesses like diabetes, hyperthyroidism, or intestinal parasites may feel hungrier and eat more, resulting in weight gain. An increased appetite can also sometimes indicate stress or boredom in cats.
Owners should monitor any significant changes in their cat’s normal food intake, preferences, or weight, as it often indicates an underlying health issue. A thorough veterinary exam can help determine the cause and appropriate treatment.
Changes in Activity Level
One of the most common signs of illness in cats is a change in their normal activity level. Sick cats tend to have a noticeable decrease in energy and become less active than usual. They may sleep more than normal, sometimes up to 20 hours a day or even more. Cats naturally sleep a lot, but extended periods of excessive sleep and lethargy can signify an underlying health issue.
You may also notice your cat moving slower or being less playful. A healthy cat is typically very energetic and interactive, but a sick cat will often lose interest in playing with toys or interacting with family members. They may spend more time hiding or quietly resting in one spot instead of actively exploring their environment. The loss of energy and refusal to play can happen gradually or quite suddenly in sick cats.
According to PetMD, “A change in energy level may seem to happen all of a sudden, or it may be a gradual process over days or weeks.” If your once energetic cat starts sleeping more, moving less, and showing no interest in play or exercise, it could be their way of telling you they are not feeling well and need to see a veterinarian.
Physical Changes
Cats experiencing illness may undergo physical changes that are noticeable upon inspection. Some common physical symptoms to look out for include:
- Dull coat – The fur may become matted, rough, flaky, or appear dirty even after grooming. This can signify nutritional deficiencies or other health issues.
- Excessive shedding – Shedding much more than usual may indicate skin problems, allergies, or hormonal imbalances.
- Bad breath – Foul breath or gingivitis can signal dental disease, kidney problems, or gastrointestinal issues.
- Muscle loss – Thinning muscles, especially around the spine or hips, can occur with various conditions like kidney disease, hyperthyroidism, and cancer.
Take note if your cat seems to have a poor, unkempt coat quality or their muscles appear less defined. Dramatic or sudden changes in physical appearance warrant a veterinary visit for diagnosis and treatment (Source).
Vocal Changes
Cats can use their voices to communicate that they are unwell. Increased vocalization, such as meowing more often or more urgently than usual, can indicate a cat is not feeling their best.
Some specific vocal signs that a cat may be sick include:
- Excessive meowing, especially meows that sound distressed or painful
- Altered meow sounds, such as a more raspy or hoarse meow
- Yowling or howling, which can signify pain or discomfort
- Growling or hissing when they previously were not aggressive
According to VCA Animal Hospitals, “Cats feel more insecure when they are ill and become more vocal and attention seeking. They know something is wrong.” (https://vcahospitals.com/know-your-pet/recognizing-signs-of-illness-in-cats)
Pay attention to any vocal changes in your cat. These can provide clues into how your cat is feeling and alert you to potential health issues that may require veterinary attention.
Bathroom Changes
One of the most common signs of illness in cats is inappropriate elimination or changes in litter box habits. According to Veterinary Centers of America (VCA) Animal Hospitals, house soiling or inappropriate urination is the top behavioral complaint among cat owners (source).
There are several bathroom changes that may indicate your cat is unwell:
- Increased or decreased frequency of urination
- Urinating outside the litter box
- Having accidents in the house
- Straining or crying out when trying to urinate
- Urinating on cool surfaces like tile floors or bathtubs
- Blood in the urine
According to the MSPCA, inappropriate urination can result from illness, stress, anxiety, or being harassed by another pet while trying to use the litter box (source). Any noticeable changes in litter box habits, especially an increase in frequency or accidents, can signify disease and require veterinary attention.
Gastrointestinal Signs
Some common gastrointestinal signs that indicate a cat is not feeling well include vomiting, diarrhea, constipation, and gas. These can point to issues like inflammatory bowel disease, infections, obstructions, or other problems with the digestive tract (Merck Veterinary Manual).
Vomiting is one of the most noticeable gastrointestinal signs in cats. Repeated vomiting or vomiting that contains blood or looks like coffee grounds can indicate a serious issue that requires veterinary attention. Cats may also vomit hairballs, but frequent vomiting of hairballs can still be a concern (Bond Vet).
Diarrhea or loose stools can occur from infections, parasites, food allergies, inflammatory bowel disease, and other issues. Severe or bloody diarrhea is an emergency. Milder diarrhea may resolve on its own, but if it persists more than a day or two, a vet visit is warranted.
On the other end of the spectrum, constipation is another common gastrointestinal sign in cats. Constipation is usually characterized by difficulty defecating, small hard stools, and infrequent bowel movements. Making dietary changes, increasing hydration, adding fiber, or giving laxatives may help relieve mild constipation.
Excessive gas or flatulence can also indicate gastrointestinal upset in cats. This may present as audible gas, gurgling sounds from the abdomen, or difficulty passing gas. Dietary adjustments and probiotics can help reduce gas (Gulf South Animal Hospital).
Respiratory Signs
Some of the most common respiratory signs that indicate a cat is not feeling well include sneezing, coughing, and nasal discharge. Frequent sneezing is often a sign of irritation or inflammation in a cat’s nasal passages and upper respiratory tract. It can be caused by infections, allergies, foreign objects stuck in the nose, or other medical conditions. Coughing is also common with upper respiratory infections as well as other lung and airway diseases like asthma or pneumonia. Cats may cough when there is inflammation in their windpipes or an accumulation of mucus. Nasal discharge tends to increase and take on a thicker, discolored appearance when a cat has an upper respiratory infection. The discharge may be clear, off-white, yellow, or greenish in color. Excessive nasal discharge is the body’s way of trying to expel bacteria or irritants from the nasal passages.
According to veterinarians, some key signs of upper respiratory infections in cats include “sneezing, nasal congestion, runny nose, coughing, and discharge from the eyes or nose.” These symptoms often get worse without treatment. Respiratory infections are very contagious among cats, so isolating the sick cat from other household pets is recommended. Seeking prompt veterinary care for diagnosis and treatment is important, as respiratory infections can lead to more serious complications if left untreated. Antibiotics, anti-inflammatory medications, and supportive care may be prescribed.
Sources:
https://www.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information/feline-health-topics/respiratory-infections
https://vcahospitals.com/know-your-pet/feline-upper-respiratory-infection
Skin and Coat Changes
Changes to a cat’s coat and skin can be indicative of illness. Some common signs to look out for include:
Itching and scratching – Cats experiencing skin irritation and itchiness will excessively scratch, lick or chew areas of their body. This could indicate allergies, skin infections, parasites like fleas or mange, or other skin diseases.
Hair loss and thinning fur – Patches of hair loss or a generally poor, thin coat can signal illness. Some causes include hyperthyroidism, Cushing’s disease, ringworm or other fungal infections.
Rashes and scabs – Skin rashes manifest as red, inflamed areas that may ooze and scab over. These could indicate an allergic reaction, mites, fungal infection or autoimmune disease.
Dull, flaky skin – Dry, flaky or greasy skin that loses its luster can accompany thyroid or kidney issues in cats.
Tracking changes to a cat’s skin and coat provides important clues about their health. Consult a vet if significant itching, hair loss, rashes or dull coat appear.
When to See the Vet
It’s important to monitor your cat closely for any changes in behavior or health, as cats are masters at hiding illness. Contact your vet right away if your cat displays any of these emergency warning signs:
- Not eating for more than 24 hours
- Repeated vomiting or diarrhea
- Difficulty breathing
- Sudden collapse or inability to stand
- Crying or whining in pain
- Bleeding from any part of the body
- Seizures or muscle tremors
Also let your vet know if you notice any of the following changes in your cat:
- Lethargy, weakness, or extreme fatigue
- Weight loss
- Changes in bathroom habits
- Changes in personality or behavior
- Skin problems or hair loss
- Excessive scratching or licking
- Coughing, sneezing, or discharge from nose/eyes
- Changes in eating or drinking habits
While individual symptoms may not require an urgent vet visit, multiple symptoms or a progression of severity over time does warrant a call to your vet. They can advise you on the best course of action for your cat’s health.