The Mystery of the Hot Cat. Why Your Feline Feels Feverish

Normal Cat Body Temperature

The average cat body temperature is between 100.5 to 102.5°F (38 to 39.2°C), with a normal range usually considered 100.4–102.8°F (38–39.3°C) (VCA Hospitals). Cats regulate their body temperature carefully, as even small changes in core body temperature can affect their health and behavior. Slight fluctuations of a degree or two throughout the day are normal as a cat’s temperature adjusts with activity levels and environmental conditions. However, significant changes in body temperature are a cause for concern and may indicate an underlying medical issue such as an infection.

Causes of Elevated Body Temperature

There are several potential causes for an elevated body temperature in cats:

Infection – Bacterial and viral infections can cause a fever as the body’s immune system responds. Upper respiratory infections, urinary tract infections, panleukopenia, and other contagious illnesses may elevate a cat’s temperature.

Inflammation – Inflammation in the body from conditions like pancreatitis, arthritis, cancer, and inflammatory bowel disease can also raise a cat’s temperature.

Trauma – Physical trauma from an injury, burn, or surgery can induce a fever as the body deals with damage and tries to heal itself.

Stress – Stress responses in cats can also increase body temperature. Situations causing anxiety like travel, loud noises, new environments, or changes in routine may cause a slight fever.

Exercise – Strenuous physical activity and exercise in cats can also temporarily raise body temperature from the exertion.

Hot environments – Exposure to high ambient temperatures in the environment can cause a cat’s body temperature to elevate as they try to cool down.

In most cases, a fever indicates an underlying illness, so it’s important to identify the root cause through diagnostic testing. Fevers don’t occur randomly in healthy cats.[1]

Diagnosing a Fever

The most accurate way to diagnose a fever in cats is by taking their temperature. A normal temperature for cats ranges from 100°F to 102.5°F. A fever is usually defined as a temperature over 103°F.

To take your cat’s temperature, you’ll need a digital rectal thermometer designed for pets. Gently lift your cat’s tail and insert the tip of the thermometer about 1 inch into the rectum. Wait until you hear the thermometer beep, indicating it has a reading. This usually takes less than 60 seconds.

In addition to checking temperature, watch for other common signs of fever in cats:

  • Warm, dry nose
  • Reduced appetite or refusing food
  • Lethargy or lack of energy
  • Drinking more water than usual
  • Shivering

Cats tend to try to hide illness. Pay close attention for subtle changes in behavior that could indicate fever. If you suspect your cat has a fever, take their temperature to confirm and contact your veterinarian if it is over 103°F.


Treating a Fever

If your cat has a fever, the first step is to take them to the vet for an examination. The vet will run tests to try to determine the underlying cause of the fever, such as infections, inflammation, cancer, etc. Common tests include bloodwork, urinalysis, imaging scans, and biopsies if needed.

Treatment depends on the cause of the fever. For example, if it’s a bacterial infection, the cat may be prescribed antibiotics. If it’s an autoimmune disorder causing inflammation, steroids may be given. Cancer would be treated differently. The vet will choose medications and therapy tailored to the specific illness causing the elevated temperature.

In general, treating the fever itself involves reducing the cat’s temperature to the normal range between 100-102° F. This is done through medications like ibuprofen for pain and fever reduction, cooling the cat with wet towels, hydrating with fluids, and monitoring their temperature. However, the underlying cause still needs to be addressed or else the fever will persist or keep returning. Work closely with your vet to identify and properly treat the source of the fever.

Some key points about treating fevers in cats:
– Visit the vet for tests to determine the cause

– Treatment addresses the underlying illness, not just fever reduction
– Reducing temperature, hydration, pain relief are part of fever management
– Never give human fever medications without asking a vet
– Cats can go downhill quickly so follow up vet care is critical

When to See the Vet

Cats vary in temperatures for what is considered an elevated fever. However, as a pet parent, you should not take the rise in temperature lightly. Some fevers can quickly become dangerous if left untreated. It’s important to monitor your cat closely and contact your vet if certain thresholds are met.

According to WebMD, you should take your cat to the vet if their fever is over 103F. This indicates a moderate to high fever that requires medical attention ( A fever this high puts cats at risk of complications from the underlying illness causing it.

You should also call or visit the vet if the fever lasts more than 2-3 days without improving. As Carolina Vet notes, prolonged fevers in cats need to be addressed to determine the cause and treat appropriately (

Finally, even if the fever itself is not dangerously high, you should still contact your vet if your cat is showing concerning symptoms along with the fever. Lethargy, not eating or drinking, vomiting, diarrhea, dehydration, or other signs of distress warrant a vet visit for evaluation and care ( Your vet can determine if your cat needs medications, fluids, or other treatment to manage their illness.

Infections Causing Fever

There are various types of infections that can cause a fever in cats. Some of the most common include:

Upper respiratory infections

Upper respiratory infections (URIs), such as the feline herpesvirus, calicivirus, Chlamydophila felis, and Bordetella bronchiseptica, often cause fever along with ocular and nasal discharge, sneezing, and congestion (VCA Animal Hospitals). URIs are highly contagious between cats, so keeping sick cats isolated is important.


Bite wounds or other injuries that become infected can result in an abscess and fever. Look for swollen, painful areas on the skin accompanied by fever. Treatment usually requires draining the abscess and antibiotics (Today’s Veterinary Practice).

Urinary tract infections

Bacterial urinary tract infections (UTIs) often cause fever along with symptoms like straining to urinate, blood in the urine, and excessive licking of the genital area. UTIs require antibiotics and sometimes urinary acidifiers or dietary changes (Carolina Veterinary Specialists).


Feline panleukopenia virus causes fever, vomiting, diarrhea, and can be life-threatening, especially in unvaccinated kittens. Supportive care and antibiotics may be given while the cat’s immune system fights the virus.

Other Causes of Fever

While infections are the most common cause of elevated temperature in cats, fevers can also indicate more serious underlying conditions. Here are some other potential causes of fever to be aware of:

Cancer – Lymphoma, leukemia and other cancers affecting the blood, bone marrow and lymph nodes can lead to fevers. The cancer causes inflammation that raises body temperature.

Arthritis – Severe arthritis, especially conditions like feline infectious peritonitis (FIP) that cause inflammation in joints, may result in fever.

Dental disease – Abscessed or infected teeth and gums can allow bacteria into the bloodstream and raise body temperature.

Poisoning – Ingestion of toxins like antifreeze, human medications, plants, and chemicals can cause fever along with other symptoms.

Trauma – Severe trauma from injuries, burns or surgeries can lead to fever as the body reacts to the damage.

Hyperthyroidism – An overactive thyroid gland speeds up metabolism, generating excess body heat and fever.

Anemia – Low red blood cell count reduces oxygen circulation, forcing the body to work harder and heat up.

Seizures – Fever can sometimes accompany or follow seizure episodes.

Blood clots – Clots that restrict blood flow and oxygen delivery may elevate body temperature.

Preventing Fevers

There are several ways to help prevent your cat from developing a fever:

Get your cat vaccinated regularly. Vaccines help prevent many common illnesses that can cause fever like feline panleukopenia, calicivirus, herpesvirus, and rabies. Follow your veterinarian’s recommendations for vaccination schedules. Keeping your cat up-to-date on vaccines is key for fever prevention.

Use monthly parasite prevention medication prescribed by your vet. Parasites like worms and fleas can cause illness and infection leading to fever. Using parasite prevention helps keep your cat protected.

Reduce stress for your cat. Stress can weaken the immune system and make cats more prone to illness and fever. Try to minimize stressful events, keep litter boxes clean, make sure your cat isn’t being harassed by other pets, and give your cat plenty of affection.

Provide a clean home environment. Scoop litter boxes daily, wash food and water bowls regularly, and clean up messes right away. Don’t allow litter boxes to become too dirty and make sure your cat has fresh, clean water at all times. This helps prevent bacterial or viral growth that could cause illness.

With proper care and prevention, you can help keep your cat healthy and avoid many common causes of fever.

Caring For a Cat With a Fever

Caring for a cat with a fever requires keeping the cat comfortable and monitoring their condition. Some tips for caring for a feverish cat include:

– Offer food and water frequently. Cats with fevers often don’t feel like eating or drinking much, but staying hydrated is important. Offer small amounts of the cat’s favorite foods and fresh water often.

– Keep the environment cool and calm. Make sure the room temperature is not too warm. Provide a quiet, dark space for the cat to rest undisturbed. Reduce noise and activity levels.

– Limit handling and activity. Let the cat rest as much as needed. Restrict playtime and only handle the cat when necessary, such as to administer medication or take to the vet. Over-exertion can raise body temperature.

Monitor the cat’s symptoms and call the vet if the fever persists more than 1-2 days, gets higher, or is accompanied by lethargy, breathing issues, or other concerning symptoms. With supportive home care and veterinary treatment if needed, feline fevers often resolve on their own.


When to Seek Emergency Care

It is crucial to seek immediate veterinary care if your cat has a fever over 104°F (40°C). A temperature this high can lead to seizures, organ damage, and even death if left untreated (source). Additionally, seek emergency care if your cat displays lethargy, seizures, vomiting, or difficulty breathing along with the fever. These are signs your cat may be battling a life-threatening illness and needs urgent medical attention.

Cats can deteriorate rapidly when ill, so do not wait to see if symptoms improve on their own. A quick vet visit can identify the underlying cause and get your cat the right treatment before their condition becomes critical. Waiting too long with a high fever or concerning symptoms can lead to a much worse prognosis for your pet.

If you cannot reach your regular vet, do not hesitate to visit an emergency veterinary clinic. They are open 24/7 and equipped to provide emergency care and stabilize critically ill pets. Time is of the essence when a cat has a dangerously high fever, so seek professional veterinary help without delay if your cat exhibits any of these emergency signs along with an elevated temperature.

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