Rheumatoid arthritis is an autoimmune condition characterized by inflammation, joint pain, stiffness and lack of mobility. Another one of the symptoms that can occur is fever, which is related to rheumatoid arthritis and juvenile rheumatoid (or idiopathic) arthritis in several ways:

Disease Activity

When your rheumatoid arthritis is active, high levels of inflammation in your body can cause a low-grade fever, about 99 to 100.9 degrees Fahrenheit. Also, rheumatoid arthritis causes severe changes in the way your immune system works, which may reduce its ability to battle infections and lead to various symptoms including fever.

Medications and Infections

Some of the drugs used to fight rheumatoid arthritis suppress the immune system and make you more susceptible to infections and resulting fever. For instance, studies show that people taking anti-TNF alpha drugs have a much greater risk of tuberculosis.

Other rheumatoid arthritis drugs that can increase your risk of infection include steroids, and some disease-modifying anti-rheumatic drugs (DMARDs) such as methotrexate and leflunomide.

Still's Disease

Still's disease precedes about 10 to 20 percent of cases of juvenile idiopathic arthritis. It can also affect adults, with symptoms usually starting between ages 20 and 35.

The symptoms include high fever; rash; achy, swollen joints; enlarged lymph nodes (adenopathy); inflammation of the tissue surrounding the (pericarditis); and inflammation of the lining of the lung (pleuritis). Often, fever is higher in the afternoon, and may last for up to two weeks.

Treating a Fever in Rheumatoid Arthritis

It's not always necessary to treat a low-grade fever. If you have it for a few days, or your temperature rises above 101 degrees, you should call your doctor right away.

These symptoms most likely indicate that you have an infection, which can quickly worsen because of your rheumatoid arthritis or the drugs you're taking. Treatment will depend on the cause of the fever.

Antibiotics

For a bacterial infection, such as strep throat, you'll need to take antibiotics. Studies show that infections acquired under methotrexate use can be safely treated with antibiotics while continuing to take this arthritis drug.

If you have tuberculosis (TB), you'll need to take three to four antibiotics daily for between six to nine months, as indicated in the Journal of the American Medical Association. You should be tested for TB before going on anti-TNF treatment for rheumatoid arthritis.

Rheumatoid Arthritis Drugs

If your fever is caused by disease activity, your doctor may recommend changing or increasing your rheumatoid arthritis drugs (including DMARDs) to better control the disease and reduce inflammation.

As far as treating fever, this approach is particularly important in Still's disease and juvenile idiopathic arthritis, where systemic fever is quite common.

Antiviral Medication

Sometimes, the culprit may be a virus such as the herpes zoster (shingles) virus. People with rheumatoid arthritis are more vulnerable to herpes zoster than the rest of the population, especially if they're taking anti-TNF alpha drugs.

Although herpes zoster may go away without treatment within a few weeks, your doctor may prescribe an antiviral such as acyclovir or famciclovir.  

Another common cause of fever is the flu virus. The Arthritis Foundation strongly recommends that people with rheumatoid arthritis get the annual flu shot. However, you should not use inhaled flu vaccines because they contain the live virus, which is very dangerous to people with autoimmune conditions.

Home Remedies

Some tried-and-true home therapies can also help to suppress a fever. Try applying a cold compress, or taking a cool shower or bath. You can also drink lots of cool liquids, especially those that have benefits for rheumatoid arthritis, such as iced green tea, or chilled berry or cherry juices.