While fevers can sometimes be mild and pass on their own, others are more serious and can indicate a serious medical condition. Today, our Wake Forest vets share the signs, symptoms, and causes of fever in cats, and the steps you should take when they happen.

How to Properly Take Your Cat's Temperature

Cats typically have a normal body temperature of 100.4º to 102.5º Fahrenheit.  A fever is characterized by a temperature of more than 102.5º F in cats. If your kitty's temperature goes beyond 106º F your pet is at serious risk of damage to their vital organs. 

Taking your cat's temperature is fairly straightforward. Simply use a digital thermometer aimed at your cat’s ear, or use a pediatric rectal thermometer for a more accurate reading. Never use an older-style mercury thermometer when taking your pet's temperature! If the thermometer breaks it can be very harmful to your kitty'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. Apply petroleum jelly to the thermometer to lubricate it, then gently insert it. It's important not to go too far as it could damage your cat's delicate rectal tissue. You may need someone to help you calmly restrain your cat while you insert the thermometer. Leave the thermometer in place for at least two minutes to get a correct reading.

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

Common Causes of Fever in Cats

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

  • Bacterial, viral, or fungal infection
  • Injury
  • Trauma
  • Certain medications
  • A tumor
  • Diseases such as lupus

Conditions that Can Cause Fever in Cats

When it comes to health conditions and infections resulting in fever, outdoor cats are far more susceptible compared to indoor cats. Some of the common conditions that cause fever in cats include:

Bobcat Fever in Cats (Cytauxzoonosis)

Bobcat fever or tick fever in cats, 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. Bobcat fever symptoms in cats can include lethargy, depression, not wanting to eat, and a high fever.

Valley Fever in Cats (Coccidioidomycosis)

Valley fever in cats is caused by the inhalation of the soil fungus Coccidioides immitis found in desert regions of the Southwestern United States. Symptoms of valley fever in cats include fever, lethargy, poor appetite, and coughing, but can progress to severe joint and back pain, seizures, and blindness.


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


Ehrlichiosis is a tick-borne condition that can lead to fever in cats. The signs of Ehrlichiosis in cats include fever, swollen lymph nodes, lethargy, decreased appetite, abnormal bruising or bleeding, and eye inflammation.

Milk Fever in Cats (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 in Cats (Bartonellosis)

This condition can be transmitted between animals and from animals to humans. In cats, the disease is typically spread through contact with flea feces. Cat scratch fever symptoms in cats include fever, swollen glands, lethargy, decreased appetite, and in some cases reproductive difficulties.


Toxoplasmosis is a serious parasitic disease that is also one of the most common. Toxoplasmosis in cats can lead to symptoms such as fever, diarrhea, cough, difficulty breathing, jaundice, and seizures, and in severe cases, this condition can be life-threatening.

Signs & Symptoms of Fever in Cats

The symptoms that your cat experiences will vary depending on their underlying condition. Some of the most common signs include:

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

What To Do If Your Cat Has a Fever

Many human medications are toxic and potentially fatal for cats. You should never give them any medications without explicit instructions from your vet to do so.

Make sure your kitty 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's fever lasts longer than 24 hours or goes above 106º F contact your vet to book an urgent appointment or visit your local emergency animal hospital.

Your vet will do a full examination of your cat to determine the cause of your pet's fever and prescribe the best treatment to help restore your cat's good health. In some cases, even after an extensive veterinary examination, the cause may not be evident and your cat could be diagnosed with a fever of unknown origin (FUO). If your cat has moderate or severe dehydration, intravenous fluids may be used to help your cat 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. 

If your cat is showing serious symptoms such as a high fever and requires urgent veterinary care, please contact our vets in Wake Forest