Chronic fatigue

What it means

Subjective feeling of tiredness characterized by a lack of energy and motivation that persists for six months or longer.

Note that chronic fatigue can be a symptom of chronic fatigue syndrome (CFS), which is characterized by profound fatigue that is not improved by bed rest and that may be worsened by physical or mental activity. Symptoms of CFS may include weakness, muscle pain, impaired memory, impaired mental concentration, and insomnia, which can result in reduced participation in daily activities.

Rare diseases that can present with this19

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category