Fibromyalgia is a chronic condition that causes widespread musculoskeletal discomfort and tenderness as well as other intrusive symptoms. It causes symptoms very similar to arthritis in many cases. 

But, unlike arthritis, fibromyalgia isn’t autoimmune or inflammatory. Current research indicates central nervous system involvement, and the American College of Rheumatology calls fibromyalgia a neurological condition. 

Having diseases like osteoarthritis, rheumatoid arthritis, lupus, and spondyloarthritis increases the risk of fibromyalgia. The vast majority of people with fibromyalgia are female, but men sometimes develop the condition as well.