Tiredness; Weariness; Exhaustion; Lethargy
Fatigue is a feeling of weariness, tiredness, or lack of energy.
Fatigue is different from drowsiness. Drowsiness is feeling the need to sleep. Fatigue is a lack of energy and motivation. Drowsiness and apathy (a feeling of not caring about what happens) can be symptoms that go along with fatigue.
Fatigue can be a normal and important response to physical activity, emotional stress, boredom, or lack of sleep. Fatigue is a common symptom, and it is usually not due to a serious disease. But it can be a sign of a more serious mental or physical condition. When fatigue is not relieved by enough sleep, good nutrition, or a low-stress environment, it should be evaluated by your health care provider.
There are many possible causes of fatigue, including:
Fatigue can also occur with the following illnesses:
Certain medicines may also cause drowsiness or fatigue, including antihistamines for allergies, blood pressure medicines, sleeping pills, steroids, and diuretics (water pills).
Chronic fatigue syndrome (CFS) is a condition in which symptoms of fatigue persist for at least 6 months and do not resolve with rest. The fatigue may be worsened with physical activity or mental stress. It is diagnosed based on the presence of a specific group of symptoms and after all other possible causes of fatigue are ruled out.
Here are some tips for reducing fatigue:
If you have long-term (chronic) pain or depression, treating it often helps the fatigue. Be aware that some antidepressant medicines may cause or worsen fatigue. If your medicnie is one of these, your provider may have to adjust the dosage or switch you to another medicine. DO NOT stop or change any medicines without first talking to your provider.
Stimulants (including caffeine) are not effective treatments for fatigue. They can make the problem worse when they are stopped. Sedatives also tend to worsen fatigue.
Contact your provider right away if you have any of the following:
Contact your provider for an appointment if you have any of the following:
You will be asked about your medical history, fatigue symptoms, and your lifestyle, habits, and feelings.
Your provider will likely perform a complete physical examination, paying special attention to your heart, lymph nodes, thyroid, abdomen, and nervous system.
Tests that may be ordered include the following:
Treatment depends on the cause of your fatigue symptoms.
Clauw DJ. Fibromyalgia. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 253.
Regehr J. Fatigue. In: Kellerman RD, Rakel DP, Heidelbaugh JJ, Lee EM, eds. Conn's Current Therapy 2023. Philadelphia, PA: Elsevier 2023:14-15.
Seller RH, Symons AB. Fatigue. In: Seller RH, Symons AB, eds. Differential Diagnosis of Common Complaints. 7th ed. Philadelphia, PA: Elsevier; 2018:chap 14.BACK TO TOP
Review Date: 6/12/2023
Reviewed By: Jacob Berman, MD, MPH, Clinical Assistant Professor of Medicine, Division of General Internal Medicine, University of Washington School of Medicine, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
Health Content Provider
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2023 A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited.