It is not known what causes fibromyalgia. It can be more common in people who have:
- inflammatory arthritis (for example, rheumatoid arthritis)
- an illness, such as a virus (or following an illness or infection)
- pain from an injury or trauma
- experienced emotional stress and depression.
For many people fibromyalgia starts without any obvious cause. Research suggests that the body may become extra sensitive in the way it signals and processes pain in people with fibromyalgia.