Fatigue

**Definition:** A feeling of exhaustion, lethargy, or decreased energy, usually experienced as a weakening or depletion of one's physical or mental resource and characterised by a decreased capacity for work and reduced efficiency in responding to stimuli. Fatigue is normal following a period of exertion, mental or physical, but sometimes may occur in the absence of such exertion as a symptom of health conditions.

**Inclusions:** - General physical deterioration - Lethargy

**Exclusions:** - Chronic fatigue syndrome - Myalgic encephalomyelitis - Postviral fatigue syndrome - pregnancy-related exhaustion and fatigue - Bodily distress disorder - Depressive disorders - Sleep-wake disorders - Bipolar or related disorders - senile fatigue - Combat fatigue - Exhaustion due to exposure - heat exhaustion