How to Tell If Your Cat Has a Fever
Understanding when your cat has a fever is essential for timely veterinary care. Cats are experts at masking illness, so knowing the signs and how to take their temperature can make all the difference. A normal feline temperature ranges from 100.4°F to 102.5°F (38–39.2°C). Anything above this range suggests a fever, also called hyperthermia.
Causes of Fever in Cats
- Infections: Bacterial, viral, or fungal infections can trigger a fever.
- Inflammation: Injuries or chronic inflammatory conditions may raise the body temperature.
- Immune-mediated diseases: Autoimmune responses can cause persistent fevers.
- Heatstroke or hot environments: Not a true fever, but raises body temperature dangerously.
- Toxins or reactions to medications: Certain chemicals and drugs can also induce fever.
Symptoms That May Indicate a Fever
- Lethargy: Low energy or sleeping more than usual.
- Loss of appetite: Refusal to eat or drink.
- Shivering or panting: Attempting to regulate body temperature.
- Decreased grooming: Lack of personal hygiene habits.
- Hiding: Isolating from people or other pets.
- Vomiting or diarrhea: Gastrointestinal upset may accompany fever.
- Behavioral changes: Increased aggression or irritability.
How to Check Your Cat’s Temperature
Rectal Thermometer: Most accurate method. Use a pediatric digital thermometer:
- Gently restrain your cat—have someone assist if necessary.
- Lubricate the thermometer tip with petroleum jelly.
- Insert it about 1 inch into the rectum carefully and wait for the beep.
- Read the temperature and gently remove the thermometer.
Digital Ear Thermometer: Less invasive, though slightly less accurate.
- Insert carefully into the horizontal ear canal.
- Follow manufacturer instructions for best accuracy.
Never force the device; if you're unsure, have your vet demonstrate the proper technique.
When to Seek Veterinary Help
If your cat’s temperature is above 102.5°F or below 99°F, consult a veterinarian. Persistent temperature above 106°F is an emergency that can cause organ failure. Treatment may include:
- Fluids: To prevent dehydration.
- Antibiotics: For bacterial infections.
- Diagnostics: Blood work and imaging for underlying causes.
Never give human medications like ibuprofen or acetaminophen—they are toxic to cats.
Environmental Considerations
Sometimes elevated temperature is due to environment, not illness.
- Warm Surroundings: Temperatures above 100°F are dangerous, especially if the cat cannot access shade or water.
- Hot Surfaces: Asphalt or locked cars can cause heatstroke.
- Thermoneutral Zone: Cats feel comfortable at 86–101°F and use behaviors like licking, panting, or stretching to cool down.
Understanding Hypothermia in Cats
Temperature below 99°F is hypothermia and can occur from cold exposure, anesthesia or shock.
- Signs: Cold skin, pale or bluish gums, slow breathing or heart rate, collapse.
- Treatment: Use external warming like blankets for mild cases, and internal heating, like warmed IV fluids, for severe cases. Avoid hairdryers.
Preventing Temperature Extremes
Ensure your cat has access to both warm spaces and cool areas as needed. Those at higher risk include:
- Kittens
- Senior cats
- Overweight cats
- Cats with chronic illnesses
Provide clean water at all times and monitor for early signs of temperature-related issues. Early detection and treatment can save your cat’s life.
