Fatigue

Alternative names:

exhaustion; lethargy; tiredness; weariness

Definition:

A feeling of lack of energy, weariness or tiredness.

Considerations:

Fatigue is not the same as drowsiness, but the desire to sleep may accompany fatigue. Apathy is a feeling of indifference; this may accompany fatigue but may also exist independently.

Fatigue represents a normal and important response to physical exertion, emotional stress, or lack of sleep.

Fatigue can also be a nonspecific symptom of a psychological or physiologic disorder. Pathologic (illness-related) fatigue is not relieved by adequate rest, adequate sleep, or removal of stressful factors. Fatigue that is not relieved by normal means, or that occurs in the absence of a known cause or other symptoms should be medically evaluated.

The pattern of fatigue may help delineate its underlying cause. Individuals who arise in the morning rested but, with activity, rapidly fatigue may have an ongoing condition or disease. Individuals who awaken fatigued and the level of fatigue remains constant throughout the day may be suffering from depression. However, these are not absolutes and chronic fatigue should be evaluated by a health care provider.

In many cases, fatigue is related to boredom, unhappiness, disappointment, lack of sleep, or hard work. Because fatigue is such a common complaint and is often caused by psychological problems, its potential seriousness is often overlooked.

Common causes:

• acromegaly
• Addison's disease
• AIDS
• chronic allergic-type disorders such as hay fever or asthma)
• anemia including iron deficiency anemia
• chronic boredom
• chronic infection such as chronic bacterial endocarditis
• congestive heart failure
• diabetes
• drugs such as antihistamines, antihypertensives, sedatives, or diuretics
• hypothyroidism
• juvenile rheumatoid arthritis
• kwashiorkor
• malignancy (cancer)
• excessive physical exertion
• poor nutrition
• rheumatoid arthritis
• systemic lupus erythematosus
• tuberculosis
• viral infections such as influenza and mononucleosis
• anxiety and depression
• grief
• sleep disorders such as insomnia
• stress (prolonged and severe)
• most types of surgery (temporary fatigue)
• infectious disease
• congestive heart failure

Note: There may be other causes of fatigue. This list is not all inclusive, and the causes are not presented in order of likelihood. The causes of this symptom can include unlikely diseases and medications. Furthermore, the causes may vary based on age and gender of the affected person, as well as on the specific characteristics of the symptom such as quality, time course, aggravating factors, relieving factors, and associated complaints. Use the Symptom Analysis option to explore the possible explanations for fatigue, occurring alone or in combination with other problems.