Fever in Dogs

Fevers are as uncomfortable for dogs as they are for people. A fever is not a sickness, though. It helps the body fight infection and inflammation. A dog may experience this elevation in body temperature due to untreated wounds, toxic exposure, viruses, or other diseases. Treatment is aimed at the underlying cause of the fever, which will often help reduce a dog's temperature back to normal.

What Is a Fever?

Fever refers to an involuntary elevation in a dog's body temperature that occurs in response to an immune trigger. It is the body's attempt to "burn out" a pathogen or other disease-causing agent. Fevers can be helpful to the healing process, but a prolonged high fever can also be dangerous.

Symptoms of Fever in Dogs

A dog's normal body temperature ranges between 101 and 102.5 degrees Fahrenheit. A higher temperature can often be detected by an attentive owner who recognizes that their dog feels warmer than usual and is not acting quite normal.

In addition to a high body temperature, which can most easily be felt in areas of sparse fur, a dog may appear unhappy or tired because it feels poorly. Both the underlying cause of the fever and the fever itself can induce pain or chills.

Causes of Fever

Fever is a symptom of an illness in the body. Fevers are most commonly caused by infections. Other potential causes include:

• Bacterial infections are responsible for most fevers in dogs. They generally occur due to a wound or abscess. Internal bacterial infections like pneumonia, leptospirosis, urinary tract infections, and tick-borne diseases can also lead to fever.
• Some fungal infections like coccidioidomycosis (valley fever), blastomycosis, histoplasmosis, and disseminated aspergillosis are known to cause fevers in dogs.
• Certain viruses lead to fever in dogs. These include canine distemper, canine adenovirus, rabies, and canine parvovirus.
• Exposure to toxins and poisons like toxic food, hazardous chemicals, and poisonous plants can trigger fevers.
• A dog may develop a low-grade fever following vaccination. Most vaccine-related fevers are mild and self-limiting. However, some dogs experience vaccine reactions that require veterinary care.
• Immune-mediated or autoimmune diseases can confuse the immune system, causing it to fight against itself with a febrile (fever) response.
• Cancer can sometimes be responsible for a dog's fever, especially leukemia, lymphoma, and liver cancer.

Hyperthermia is not quite the same as a fever; it's an elevation in body temperature due to external heat. Hyperthermia may lead to heatstroke.

Diagnosing Fever in Dogs

A dog's body temperature can accurately be measured using a rectal thermometer. Because fever is merely an indication of illness, your vet's diagnostic procedures may also include blood work, fecal and/or urinary analyses, x-rays, and other tests to identify the infection or illness underlying the fever.

Treatment

The exact treatment for a fever depends on the underlying cause. You can help your vet by providing detailed information about your dog's recent activities. Be sure to mention injuries, exposure to toxins, and contact with other animals.

Most fever cases require some form of supportive care to manage symptoms and promote recovery. This may involve hospitalization, intravenous fluids, and medications. Antibiotics are used for bacterial infections and antifungal drugs are used to treat fungal infections, but additional treatment may be needed to address the source of the infection.

Prognosis for Dogs with Fever

Because fever is not a disease or condition on its own, the prognosis for a dog with a fever depends on the reason for the febrile response, which can vary in severity from mildly concerning to life-threatening.

How to Prevent Fevers

Since most fevers in dogs are caused by infections, promptly treating a dog's wounds will help stave off its febrile immune response by preventing the growth of infectious pathogens. Toxic exposure and attentive wellness care are additional ways to help prevent fever in dogs. Regular vaccinations can help avoid viral illnesses that can cause fevers.

Other causes of fever, such as autoimmune diseases or cancer, are not preventable but are less likely when a dog receives a nutritious diet, exercise, and loving companionship.