Fibromyalgia (FM) is characterized by chronic, widespread, achy musculoskeletal pain that occurs throughout the body. FM impacts the central nervous system, which affects the way the brain processes messages.

It is the second most common rheumatic disorder after osteoarthritis affecting 2–8% or millions of Americans. Women are diagnosed with fibromyalgia more frequently than men (about 80% vs. 20%), and it is more common in young to middle-aged women.