context: Your joints are swollen and stiff. Your muscles also ache, and you're exhausted. Are these symptoms related? They could be signs that you have rheumatoid arthritis ( RA) and fibromyalgia, two health problems that sometimes happen together. If you have one of them, you are more likely to have the other. Only about 2% of adult Americans have fibromyalgia. But it's more common among people who have RA. Research shows that between 10% and 20% of them also have fibromyalgia. Experts are still studying the reason for the relationship. But they think that several factors play a role. In healthy people, the immune system is the first line of defense against germs, viruses, and other invaders. But RA is an autoimmune disease. That means the immune system attacks healthy tissue in your body, in this case your joints. As a result, the joints become painful and swollen. You may also feel tired. Fibromyalgia isn't an autoimmune disease. But its symptoms are similar. It also causes pain, stiffness, and fatigue. Doctors aren't sure what causes fibromyalgia. One theory is that an imbalance in brain chemicals makes you more sensitive to pain. The same pressure that other people think is normal may feel tender or painful to you. Why is that? Your genes may be part of the reason. Or something may change the way your body sends and receives pain signals. For example, studies suggest the constant pain may rev up your nervous system. The result is you become more sensitive to pain. Another link may be inflammation. which involves part of the body becoming swollen, red, hot and painful. It's the main problem in RA. Fibromyalgia isn't considered an inflammatory condition. But chronic inflammation could play a role. RA and fibromyalgia also share common risk factors. Your lifestyle, weight, and stress level may all raise your chances for both conditions. There's no one test for fibromyalgia. Doctors make that diagnosis if you have widespread pain that's not from another medical condition for more than 3 months. Because its symptoms overlap with other conditions, it's often hard to spot. On average, it takes 5 years to diagnose fibromyalgia. Many fibromyalgia symptoms are like those of RA. But there are some key differences: RA causes inflammation in the joints. The pain can come and go. With fibromyalgia, the ache is constant, and it happens all over your body. You feel dull pain that lasts at least 3 months. With fibromyalgia, you often feel tenderness when someone touches you. It can also hurt to sit for 45 minutes. It's important to get diagnosed. If you have both conditions, your doctor may chalk up the fibromyalgia pain to your RA. As a result, you may get stronger or higher doses of RA medicines than you may need. Talk to your doctor if you think you may have fibromyalgia. Doctors prescribe different drugs for RA and fibromyalgia. If you have RA, the medicines you need depend on how bad your disease is. They include: Nonsteroidal anti-inflammatory drugs ( NSAIDs), such as ibuprofen and naproxen. Steroids. These prescription medications ease inflammation. Disease-modifying antirheumatic drugs ( DMARDs). These drugs turn down your immune system. They relieve symptoms and prevent joint damage. Biologic agents. This new class of DMARDs targets specific parts of your immune system. If you have fibromyalgia, some drugs can ease the pain and help you sleep better: Over-the-counter pain relievers, such as acetaminophen and naproxen ( Aleve). Antidepressants. These medications can ease aches and fatigue. They can also help you get a better night's rest. Anti-seizure medicines. Drugs that treat epilepsy can give you relief by making you less sensitive to pain. Some lifestyle changes and treatments help with both RA and fibromyalgia: Exercise: It may be the last thing you feel like doing. But aerobic exercise, activities that keep your heart rate up, can ease pain by producing calming, pain-fighting chemicals. Aim for 30 minutes 2 to 3 times a week. Jogging, biking, and brisk swimming are some good choices. Sleep: A good night's rest may help ease fibromyalgia and RA symptoms. To improve your sleep, try to go to bed and get up at around the same time each day. Also avoid caffeine and alcohol in the late afternoon and evenings. Before bedtime, unwind with a relaxing activity, such as taking a warm bath or listening to soothing music. Physical and occupational therapy: Physical therapists teach you exercises to improve your strength, flexibility, and stiffness. Occupational therapists offer ways to do daily tasks with less pain.