If your cat is running a fever it may indicate an underlying health problem that requires urgent treatment. Today, our Los Angeles vets explain some of the causes and symptoms of fevers in cats and what to do if your cat has a fever.

Fever in Cats

As with people, cats will often develop a fever if their immune system is fighting off an infection or disease. The normal temperature range for cats is around 100.4º to 102.5º Fahrenheit.  A fever is characterized by a temperature of more than 102.5º F in cats.

If your feline friend shows any of the signs of fever below it is essential to seek veterinary care. Cats that develop a fever higher than 106º F are at serious risk of damage to their vital organs. 

Symptoms of Fever in Cats

Depending on the underlying cause, this is how to tell if your cat has a fever: 

  • Lack of appetite
  • Weakness or lethargy
  • Shivering 
  • Rapid heart rate
  • Decreased activity 
  • Decreased drinking
  • Dehydration 
  • Poor grooming
  • Vomiting
  • Diarrhea 

How To Take Your Cat's Temperature

Taking your cat's temperature is a simple process. Simply aim a digital thermometer at your cat's ear for a more accurate reading, or use a pediatric rectal thermometer.When taking your pet's temperature, never use an old-fashioned mercury thermometer! If the thermometer breaks, it can be extremely dangerous to your cat's health.

A pediatric rectal thermometer is the best way to accurately measure your pet's temperature and determine whether your cat has a fever.Lubricate the thermometer with petroleum jelly before inserting it gently. It's critical not to overdo it because it could harm your cat's delicate rectal tissue. You may require the assistance of another person to calmly restrain your cat while inserting the thermometer.To get an accurate reading, leave the thermometer in place for at least two minutes.

If you think that your cat may have a fever but you are uncomfortable taking their temperature, contact your veterinarian right away to book an appointment. Your vet will be able to quickly assess your kitty's temperature and overall state of health.

Causes of Fever in Cats

Fevers generally occur in cats when their immune system is activated by conditions such as:

  • Bacterial and viral infections
  • Fungal infection
  • Internal injury
  • Trauma
  • Parasites
  • Autoimmune disease
  • Certain medications
  • A tumor
  • Immune-mediated inflammatory disease
  • Poisoning
  • Metabolic disorders
  • Endocrine disorders

Conditions that Can Cause Fever in Cats

Outdoor cats are at the highest risk for exposure to diseases than indoor cats. There are a number of serious conditions that can cause fever in cats, including:

Bobcat Fever in Cats (Cytauxzoonosis) 

Bobcat fever is an acute, sometimes fatal disease in cats caused by the bite of a tick infected with the Cytauxzoon felis parasite. This condition often strikes healthy, young adult cats that spend time outdoors.

Valley Fever (Coccidioidomycosis) 

Bobcat fever is a potentially fatal disease caused by the bite of a tick carrying the Cytauxzoon felis parasite. This condition frequently affects healthy young adult cats who spend time outside.


Haemobartonellosis is an antibiotic-resistant bacterial blood infection seen in cats. This condition often leads to urinary tract infections and pneumonia that are very hard to treat.


Ehrlichiosis is a disease spread by ticks that can cause fever in cats. Fever, swollen lymph nodes, lethargy, decreased appetite, unusual bruising or bleeding, and eye inflammation are symptoms of ehrlichiosis in cats.

Milk Fever (Eclampsia) 

Eclampsia typically occurs in cats approximately 4 weeks after giving birth to kittens. Early signs of milk fever in cats include a stiff walk, restlessness and excessive panting.

Cat Scratch Fever (Bartonellosis) 

Animals and humans can both contract this condition from one another. Usually, contact with flea feces causes the disease to spread to cats. Cat scratch fever symptoms include fever, swollen glands, lethargy, decreased appetite, and occasionally problems getting pregnant.


One of the most widespread parasitic illnesses is this one. When toxoplasmosis in cats is severe, it can cause life-threatening symptoms like fever, diarrhea, coughing up blood, difficulty breathing, jaundice, and seizures.

What To Do If Your Cat Has a Fever

It is important to NEVER give your cat human medications without the explicit advice of a veterinarian! Many human medications, such as acetaminophen, can be extremely toxic to cats.

Make sure your cat stays hydrated by ensuring that they have easy access to fresh clean water and make sure they have a comfortable place to relax. 

If your cat has a fever that lasts longer than 24 hours or goes above 106º F contact your veterinarian to book an urgent appointment or visit your local emergency animal hospital right away.

Your veterinarian will perform a thorough examination of your cat to determine the cause of the fever and prescribe the best treatment to help restore your cat's health. Even after a thorough veterinary examination, the cause of your cat's fever of unknown origin (FUO) may not be obvious in some cases. If your cat is dehydrated to a moderate or severe degree, intravenous fluids may be administered to help him feel better and fight off illness.

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding people or pets. Always follow your doctor's advice regarding asthma or other allergy symptoms. 

At Rancho Park Veterinary Clinic in Los Angeles, our vets can provide emergency services for pets. If your cat requires urgent care, contact us right away.