Although rheumatoid arthritis (RA) and fibromyalgia are two different diseases, it’s not uncommon for people to have both conditions at once. Whereas only about 5 percent of the general population has fibromyalgia, the number increases to about 20 percent in people who have RA.

“The fibromyalgia and RA combination is difficult,” wrote a myRAteam member. “I have trouble figuring out which symptoms belong to which issue.”

If you have RA and cannot explain some of the pain or symptoms you are experiencing, it may be due to fibromyalgia.

What Are Rheumatoid Arthritis and Fibromyalgia?

Rheumatoid arthritis is an autoimmune disease. The immune system usually protects our bodies from disease-causing microorganisms like viruses and bacteria. It destroys these germs by using specialized proteins called antibodies. Sometimes, however, the immune system can mistakenly attack healthy parts of the body. This is called autoimmunity. In RA, antibodies attack the joints, which causes painful swelling called inflammation. This immune response can damage the joints of the body and cause long-lasting, chronic pain.

By contrast, fibromyalgia does not involve the immune system and is considered a noninflammatory disease. Fibromyalgia involves the nervous system. Symptoms of fibromyalgia include:

• Widespread pain all over the body
• Cognitive symptoms (“brain fog”)
• Sleep problems
• Fatigue

This disease is not life-threatening, but it can cause pain and depression that can impact your quality of life. Though researchers don’t yet know why, fibromyalgia is much more common in people experiencing other rheumatic diseases, such as RA.

Differences Between Rheumatoid Arthritis and Fibromyalgia

Though RA and fibromyalgia have different causes, widespread pain is a common symptom for both. A study asking people with fibromyalgia and RA how they experience symptoms showed that “patients identified as having fibromyalgia share many pain properties with patients with rheumatoid arthritis.”

Fibromyalgia also causes hyperalgesia, an increased sensitivity to pain. Because of this, fibromyalgia can make RA pain seem worse. Alternatively, pain from RA can mask the presence of fibromyalgia. Therefore, it may be difficult to diagnose fibromyalgia when RA pain is already present.

“I can't tell if it's the fibromyalgia or the RA because they mimic each other,” a myRAteam member shared. “So it's so hard to explain to people like nurses and doctors which is which.”

There may be some ways to tell the difference between RA and fibromyalgia pain. One study asking people to describe their RA or fibromyalgia pain suggests that fibromyalgia causes more pain in the back, neck, hands, thighs, and arms than RA. People with fibromyalgia also described more tenderness to touch, more tender points, and greater difficulty sitting for 45 minutes. Since RA causes pain in the joints, pain elsewhere in the body can be a sign of fibromyalgia.

“I have both and I know the difference for me is when my muscles, skin, and even hair hurt, it is my fibromyalgia,” another myRAteam member shared. “When it is a deep ache and shooting pain with swelling in my joints, it's my RA.”

Pain may feel different for each person, as another myRAteam member described: “For me, the joint pain and tendon swelling is RA while the muscle knots and tightness are fibromyalgia.”

Knowing the difference between RA and fibromyalgia pain is important to receive proper health care.

Fibromyalgia Affects Rheumatoid Arthritis

The relationship between RA and fibromyalgia is not fully understood and continues to be studied. Some researchers suggest fibromyalgia happens more often in people with RA because of increased inflammation from RA. More inflammation may lead to central sensitization, hypersensitive responses to stimuli in the central nervous system. This hypersensitivity creates stronger pain signals in the nervous system and drives the pain and tenderness experienced in fibromyalgia.

Some studies show that having both RA and fibromyalgia can affect disease symptoms and responses.

• A study of people with RA, fibromyalgia, or both found that people with both diseases were more likely to experience seizures.
• Having both RA and fibromyalgia costs more money for people seeking treatment than for those with just one of the conditions.
• People with fibromyalgia and RA are less likely to achieve RA remission using disease-modifying antirheumatic drugs (DMARDs).

Researchers have found that the disease severity is the same for people with RA and people with both RA and fibromyalgia. DMARDs are still effective for treating RA in people who also have fibromyalgia. But the untreated symptoms associated with fibromyalgia might make a person with both diseases feel like they are not getting any better. Since DMARDs only treat RA, it is important to also get treatment for fibromyalgia.

Lab tests can help determine if an RA treatment is working. Blood tests and X-rays can show the health of your joints and whether an RA treatment is working. If these tests show that an RA treatment is effective, continued widespread pain could be due to fibromyalgia.

The diagnosis of fibromyalgia currently depends on a doctor examining your medical history, understanding your symptoms, and ruling out other diseases. Since RA pain might mask fibromyalgia pain, this can be complicated. There is no diagnostic test for fibromyalgia. Fortunately, recent research is exploring promising options for diagnostic testing that could be helpful in the future.

Treatments for RA and Fibromyalgia

There is currently no cure for these diseases, but several treatments can help fight the symptoms.

Treatment of RA includes:

• Nonsteroidal anti-inflammatory drugs (NSAIDs), such as Advil (ibuprofen) and Aleve (naproxen) to reduce inflammation
• DMARDs and biologics to control the immune system
• Physical therapy or occupational therapy for pain management

Treatment of fibromyalgia includes:

• Pain medications or NSAIDs
• Antidepressants, like Cymbalta (duloxetine)
• Antiseizure medications, like Neurontin (gabapentin)
• Psychotherapy
• Cognitive behavioral therapy
• Natural treatments, like massage or acupuncture

Medications that reduce pain, like NSAIDs, can be helpful for treating symptoms of both RA and fibromyalgia. Research is limited on how different medications interact, so speak with your doctor if taking multiple medications is necessary.

Lifestyle Habits for Rheumatoid Arthritis and Fibromyalgia

Though painful symptoms can make exercise difficult, physical activity is important for managing both RA and fibromyalgia. “I do water aerobics and water Zumba. That's about all I can tolerate as I cannot stand or walk very long. It helps the stiffness. Makes me tired but less fatigue,” a myRAteam member wrote.

Starting with simple exercises and working with a physical or occupational therapist can help to limit pain.

Several myRAteam members with RA and fibromyalgia recommend baths for soothing discomfort. One member recommended a hot bath, then getting under a warm blanket. Another suggested adding hot Epsom salts to your bath.

An anti-inflammatory diet may also be helpful for both RA and fibromyalgia. The most popular forms of these diets are the Mediterranean diet, a high-fiber diet, and a vegan diet.

Talk With Others Who Understand

By joining myRAteam, you can become part of the social network for people with rheumatoid arthritis and their loved ones. On myRAteam, more than 146,000 members come together to ask questions, give advice, and share their stories with others who understand life with RA.

Are you living with RA and fibromyalgia? Share your experience in the comments below, or share your story on your myRAteam or MyFibroTeam.