Causes

Doctors don't know why some people develop fibromyalgia and others don't. There appears to be a genetic component because the condition tends to run in families. In some people, it may be triggered by specific events, injuries or illnesses.

Why does it hurt?

Researchers believe repeated nerve stimulation causes changes in the brain and spinal cord of people with fibromyalgia. These changes include an abnormal increase in levels of certain chemicals in the brain that signal pain. In addition, the brain's pain receptors seem to develop a sort of memory of the pain and become sensitized, meaning they can overreact to painful and nonpainful signals.