Fatigue is a feeling of tiredness or exhaustion or a need to rest because of lack of energy or strength.

Fatigue may result from overwork, poor sleep, worry, boredom, or lack of exercise. It is a symptom that may be caused by illness, medicine, or medical treatment such as chemotherapy. Anxiety or depression can also cause fatigue.

Current as of: March 12, 2014

Author: Healthwise Staff

Medical Review: William H. Blahd, Jr., MD, FACEP - Emergency Medicine & David Messenger, MD