The Fever Response

How to Take Your Cats Temperature

Our pets are an important and rewarding part of our lives. When Mr. Kitty comes down with a fever, we feel concern and want to make our feline friend all better.

What Is Fever?
Fever is defined as an elevated internal body temperature due to a reset of the temperature control center in the brain. Chemicals known as pyrogens, fever producers, circulate to the brain and reset the bodys thermostat in the hypothalmus. Pyrogens also increase production of prostaglandins that directly alter the brains temperature control center. Pyrogens can be produced by infectious agents such as bacteria, viruses, funguses, and parasites, by antigen/antibody complexes, tissue damage, and certain drugs.

Fever is different from hyperthermia, which is a high internal body temperature due to internal heat production (strenuous exercise) or exposure to high outdoor temperatures (kitty confined in a hot vehicle). Joanna Guglielmino, a feline veterinarian in Federal Way, Washington, says, The high normal temperature in a cat is 102.5. If you took a cats temperature every two hours, you would find a slight fluctuation in body temperature. But a normal cat should have a temperature ranging from 100.5 to 102.5.

Signs of Fever
Since cats are unable to tell us when and where it hurts, cat owners must be observant. If Mr. Kitty is listless, withdrawn, not eating, has muscle aches or pains and a rapid breathing rate, fever may be involved. However, since those signs may be an indication of other disorders, we dont want to assume its a fever, says Guglielmino, who is also the president of the American Association of Feline Practitioners. The cat should have a thorough examination by his veterinarian to determine the cause of the illness and provide supportive care. Any cat that is lethargic and not eating or drinking can become dehydrated quickly.

Early evaluation is extremely important for your cats well being and for your peace of mind.

Human Medicine: Dangerous?
If kitty is found to have a fever, is it appropriate to try to lower the temperature with human anti-pyretic, or fever lowering, medicine?

According to Guglielmino, most veterinarians do not try to lower the fever with anti-pyretic medication (like aspirin) but instead try to identify the cause of the fever and specifically treat the disease. Fever may be beneficial in that it stimulates the bodys immune response by activating white blood cells and inhibiting microbe growth. And human medicines that lower fever can have very serious side effects in cats. We rarely use aspirin for fever, says Guglielmino, who explains that it can be used but only with close veterinary supervision for conditions such as arthritis pain and blood clot prevention in heart disease. Cats metabolize aspirin slowly. It is used in very low doses, a small fraction of the human dosage, and no more frequently than every two-to-three days.

Some human alternatives to aspirin can even cause death in cats. Cats do not have an efficient glucuronyl transferase, a liver enzyme needed to break down acetaminophen to non-toxic by-products. Acetaminophen, contained in Tylenol and other medications, should never be given to a cat. As little as one-half of a human tablet can cause the death of a cat, says Guglielmino. Cats do not tolerate other non-steroidal anti-inflammatory drugs, such as ibuprofen, either. Ibuprofen can be lethal to cats because it damages the kidneys and can cause severe gastric (stomach) ulcerations.

Do veterinarians ever try to lower the temperature in a feverish cat? I would be very concerned if the fever is extremely high, say 106.5, where there is a danger of seizures and brain damage occurring. Some procedures Guglielmino uses in treating a fever include intravenous fluids, wetting down the tail and the pads of the feet, and continuing to look for the source of the fever through blood tests, urinalysis, and radiographs. If in the rare case where such treatments didnt bring the fever down and the fever was unrelenting, I would consider an anti-pyretic medication.