Constant Fatigue — Causes, Related Conditions & Affordable Treatment

Constant Fatigue can be associated with multiple conditions. Consult a healthcare provider to determine the cause and appropriate treatment.

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About Fatigue (the broader symptom)

This summary describes Fatigue, the broader symptom. Constant Fatigue is a more specific topic.

What is fatigue?

Fatigue is a feeling of weariness, tiredness, or lack of energy. It can interfere with your usual daily activities. Fatigue can be a normal response to physical activity, emotional stress, boredom, or lack of sleep. But sometimes it can be a sign of a mental or physical condition. If you have been feeling tired for weeks, contact your health care provider. They can help you find out what's causing your fatigue and recommend ways to relieve it.

What causes fatigue?

Fatigue itself is not a disease; it's a symptom. It can have many different causes, including pregnancy and various medical problems, treatments, and lifestyle habits such as:

Medical problems: Chronic (long-lasting) diseases such as diabetes, COPD (chronic obstructive pulmonary disease), and heart, liver, kidney and thyroid diseases

Untreated pain and diseases like fibromyalgia

Anemia

Infections

Parkinson's disease

Sleep apnea and other sleep disorders

Recent stroke

Mental disorders such as depression and anxiety

Treatments: Cancer treatments such as chemotherapy, radiation, and bone marrow transplants

Recovering from major surgery

Taking certain medicines, such as antidepressants, antihistamines, and medicines for nausea and pain

Lifestyle habits: Not getting enough sleep

Staying up too late

Drinking too much alcohol

Substance use

Having too much caffeine (which can keep you from getting a good night's sleep)

Getting too little or too much exercise

Overwhelming fatigue is part of a disorder called myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). The fatigue caused by this disorder is different from a tired feeling that goes away after you rest. Instead, the fatigue in ME/CFS lasts a long time, does not get better with rest, and limits your ability to do ordinary daily activities.

What can I do to manage fatigue?

If you've had fatigue that does not get better after several weeks, call your provider. They will ask questions about your sleep, daily activities, appetite, and exercise. They will likely do a physical exam and order lab tests. Once they decide on a diagnosis, they can tell you what treatments might help.

You can also make some lifestyle changes to feel less tired:

Get regular physical activity

Improve your sleep habits

Stop smoking (if you smoke), since smoking is linked to many diseases that can cause fatigue

Manage stress

Eat a healthy diet and avoid alcohol

It also may be helpful for you to keep a fatigue diary. This can help you find patterns throughout the day, such as when you feel more tired and when you have more energy. It can also help you plan for activities that may give you more energy.

NIH: National Institute on Aging

Source: MedlinePlus, National Library of Medicine. MedlinePlus topic page. Topic date: 03/08/2010. MedlinePlus file date: 10/15/2026 02:30:37.

Conditions related to Fatigue

These conditions are associated with Fatigue, the broader symptom.

This is not medical advice. Talk with your doctor or pharmacist.

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