You’re tired, weak, exhausted, weary, worn out. You have a lack of energy and consequently feel distressed. You’re not functioning as you should. This condition is called fatigue, and everyone feels it at times.
Acute fatigue is tiredness or lethargy that occurs occasionally and lasts for a short time. Rest may help ease acute fatigue and let you return to your normal activities.
Chronic fatigue syndrome (CFS) is a disorder that causes extreme, extended fatigue. This fatigue is not the kind of tired feeling that goes away after you rest. Instead, it lasts a long time and limits your ability to do ordinary daily activities. Fatigue may also accompany other conditions, including pregnancy, anemia, or cancer, or may result from medicines or emotional problems. Although fatigue can be common, if it is affecting you ability to function normally consult your health care provider. He or she can usually help find the cause and recommend ways to relieve it.