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Fatigue medical definition: Fatigue – Mayo Clinic

Fatigue: MedlinePlus Medical Encyclopedia

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:

  • Anemia (including iron deficiency anemia)
  • Depression or grief
  • Iron deficiency (without anemia)
  • Medicines, such as sedatives or antidepressants
  • Persistent pain
  • Sleep disorders such as insomnia, obstructive sleep apnea, or narcolepsy
  • Thyroid gland that is underactive or overactive
  • Use of alcohol or drugs, such as cocaine or narcotics, especially with regular use

Fatigue can also occur with the following illnesses:

  • Addison disease (a disorder that occurs when the adrenal glands don’t produce enough hormones)
  • Anorexia or other eating disorders
  • Arthritis, mainly adult or juvenile rheumatoid arthritis
  • Autoimmune diseases such as systemic lupus erythematosus
  • Cancer
  • COVID-19
  • Diabetes
  • Fibromyalgia
  • Heart failure
  • Infection, especially one that takes a long time to recover from or treat, such as bacterial endocarditis (infection of the heart muscle or valves), parasitic infections, hepatitis, HIV/AIDS, tuberculosis, and mononucleosis
  • Kidney disease
  • Liver disease
  • Malnutrition

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:

  • Get enough sleep each night.
  • Make sure your diet is healthy and well-balanced, and drink plenty of water throughout the day.
  • Exercise regularly.
  • Learn better ways to relax. Try yoga or meditation.
  • Maintain a reasonable work and personal schedule.
  • Change or reduce your stressors, if possible. For example, take a vacation or resolve relationship problems.
  • Take a multivitamin. Talk to your provider about what is best for you.
  • Avoid alcohol, nicotine, and drug use.

If you have long-term (chronic) pain or depression, treating it often helps the fatigue. Be aware that some antidepressant drugs may cause or worsen fatigue. If your drug is one of these, your provider may have to adjust the dosage or switch you to another drug. 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:

  • Confusion or dizziness
  • Blurred vision
  • Little or no urine, or recent swelling and weight gain
  • Thoughts of harming yourself or of committing suicide

Call your provider for an appointment if you have any of the following:

  • Unexplained weakness or fatigue, especially if you also have a fever or unintentional weight loss
  • Constipation, dry skin, weight gain, or you cannot tolerate cold
  • Wake up and fall back to sleep many times during the night
  • Headaches often
  • Are taking medicines, prescribed or non-prescribed, or using drugs that may cause fatigue or drowsiness
  • Feel sad or depressed
  • Insomnia

Your provider will perform a complete physical examination, paying special attention to your heart, lymph nodes, thyroid, abdomen, and nervous system. You will be asked about your medical history, fatigue symptoms, and your lifestyle, habits, and feelings.

Tests that may be ordered include the following:

  • Blood tests to check for anemia, diabetes, inflammatory diseases, and possible infection
  • Kidney function tests
  • Liver function tests
  • Thyroid function tests
  • Urinalysis

Treatment depends on the cause of your fatigue symptoms.

Tiredness; Weariness; Exhaustion; Lethargy

Clauw DJ. Fibromyalgia, chronic fatigue syndrome, and myofascial pain. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 258.

Lindemann JC. Fatigue. In: Kellerman RD, Rakel DP, eds. Conn’s Current Therapy 2021. Philadelphia, PA: Elsevier 2021:14-15.

Seller RH, Symons AB. Fatigue. In: Seller RH, Symons AB, eds. Differential Diagnosis of Common Complaints. 7th ed. Philadelphia, PA: Elsevier; 2018:chap 14.

Updated by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

Causes, Diagnosis, Treatment & More

Fatigue: Causes, Diagnosis, Treatment & More

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Medically reviewed by Elaine K. Luo, M.D. — By Krista O’Connell — Updated on April 18, 2023

Fatigue can occur with many different mental and physical health conditions. Some causes can be serious. You may be able to relieve fatigue with lifestyle changes to exercise, diet, and sleep.

Fatigue is a term used to describe an overall feeling of tiredness or lack of energy. It isn’t the same as simply feeling drowsy or sleepy. When you’re fatigued, you have no motivation and no energy. Being sleepy may be a symptom of fatigue, but it’s not the same thing.

Fatigue is a common symptom of many medical conditions that range in severity from mild to serious. It’s also a natural result of some lifestyle choices, such as lack of exercise or poor diet.

If your fatigue doesn’t resolve with proper rest and nutrition, or you suspect it’s caused by an underlying physical or mental health condition, see your doctor. They can help diagnose the cause of your fatigue and work with you to treat it.

There are many potential causes of fatigue. They can be divided into three general categories:

  • lifestyle factors
  • physical health conditions
  • mental health issues

Lifestyle factors

If you’re experiencing fatigue, your activities and other lifestyle choices may be the root cause. For example, fatigue can result from:

  • physical exertion
  • lack of physical activity
  • lack of sleep
  • being overweight or obese
  • periods of emotional stress
  • boredom
  • grief
  • taking certain medications, such as antidepressants or sedatives
  • using alcohol on a regular basis
  • using illicit drugs, such as cocaine
  • consuming too much caffeine
  • not eating a nutritious diet

Physical health conditions

Many medical conditions can also cause fatigue. Examples include:

  • anemia
  • arthritis
  • fibromyalgia
  • chronic fatigue syndrome
  • infections, such as cold and flu
  • Addison’s disease, a disorder that can affect your hormone levels
  • hypothyroidism, or underactive thyroid
  • hyperthyroidism, or overactive thyroid
  • sleep disorders, such as insomnia
  • eating disorders, such as anorexia
  • autoimmune disorders
  • congestive heart failure
  • cancer
  • diabetes
  • kidney disease
  • liver disease
  • chronic obstructive pulmonary disease (COPD)
  • emphysema

Mental health issues

Mental health conditions can also lead to fatigue. For example, fatigue is a common symptom of anxiety, depression, and seasonal affective disorder.

You should make an appointment with your doctor if you’re feeling fatigued and you:

  • can’t think of anything that might account for your fatigue
  • have a higher-than-normal body temperature
  • have experienced unexplained weight loss
  • feel very sensitive to colder temperatures
  • regularly have trouble falling or staying asleep
  • believe you may be depressed

If you’ve made efforts to address the most common lifestyle causes, such as lack of rest, poor eating habits, and stress, without success, and your fatigue has continued for two weeks or more, make an appointment with your doctor.

In some cases, your fatigue might be caused by a serious medical condition. Go to the hospital immediately if you experience fatigue along with any of the following symptoms:

  • rectal bleeding
  • vomiting blood
  • severe headache
  • pain in your chest area
  • feelings of faintness
  • irregular heartbeat
  • shortness of breath
  • severe pain in your abdominal, back, or pelvic region
  • thoughts of suicide or self-harm
  • thoughts of harming another person

Your doctor’s recommended treatment plan will depend on what’s causing your fatigue. To make a diagnosis, they will likely ask you questions about:

  • the nature of your fatigue, including when it started and whether it gets better or worse at certain times
  • other symptoms that you’ve been experiencing
  • other medical conditions that you have
  • your lifestyle and sources of stress
  • medications that you’re taking

If your doctor suspects you have an underlying medical condition that’s causing your fatigue, they may order some medical tests. For example, they may order blood or urine tests.

A number of measures can help lessen fatigue caused by daily activities. To help boost your energy levels and overall health:

  • drink enough fluids to stay hydrated
  • practice healthy eating habits
  • exercise on a regular basis
  • get enough sleep
  • avoid known stressors
  • avoid a work or social schedule that’s overly demanding
  • take part in relaxing activities, such as yoga
  • abstain from alcohol, tobacco, and other illicit drugs

These lifestyle changes may help ease your fatigue. It’s also important to follow your doctor’s recommended treatment plan for any diagnosed health conditions. If left untreated, fatigue can take a toll on your physical and emotional well-being.

Last medically reviewed on May 2, 2019

How we reviewed this article:

Healthline has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.

  • Always tired? 7 hidden causes for your fatigue. (2017).
    health.clevelandclinic.org/always-tired-7-hidden-causes-for-your-fatigue
  • Fatigue in older adults. (2016).
    nia.nih.gov/health/fatigue-older-adults
  • Mayo Clinic Staff. (2018). Fatigue. https://www.mayoclinic.org/symptoms/fatigue/basics/definition/sym-20050894

Our experts continually monitor the health and wellness space, and we update our articles when new information becomes available.

Current Version

Apr 18, 2023

Written By

Krista O’Connell

Edited By

Frank Crooks

May 2, 2019

Medically Reviewed By

Elaine K. Luo, MD

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Medically reviewed by Elaine K. Luo, M.D. — By Krista O’Connell — Updated on April 18, 2023

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symptoms, diagnosis, treatment of chronic fatigue – Department of Neurology NCC No. 2 (Central Clinical Hospital RAS)

Chronic Fatigue Syndrome (CFS) is a disease that is characterized by an endless feeling of fatigue, loss of strength, overwork, which does not go away even after sound sleep and long rest. Psycho-emotional stress on the human nervous system is the main cause of this disease. Residents of megacities aged 25 to 45 years are most susceptible to chronic fatigue syndrome, and women suffer more from this disease. Until recently, it was believed that only adults were susceptible to the disease, but now the diagnosis of “chronic fatigue syndrome” has begun to haunt children, especially of school age.

Causes of chronic fatigue.

Until now, the exact causes leading to chronic fatigue syndrome have not yet been established. However, risk factors that can provoke the onset of this disease exist:

  • Wrong lifestyle (frequent lack of sleep, lack of sunlight and fresh air, nicotine and alcohol use, etc.)
  • Chronic diseases (lead to emaciation)
  • Psychological disorders (constant stress, frequent depression, anxiety)
  • Unbalanced diet (poor quality food, excess or lack of food, lack of vitamins)
  • Unfavorable environment (ecological situation in cities is much worse than in rural areas)
  • Infections and viruses (the constant struggle of the body with viruses leads to general fatigue)

Symptoms of the disease.

A distinctive feature of chronic fatigue is constant overwork, which does not disappear after a sound sleep and a long rest. This painful condition can last for more than six months.

Other symptoms of chronic fatigue:

  • Insomnia
  • Migraine
  • Fatigue
  • Decreased immunity
  • Spinal and muscular pain
  • Mental impairment
  • Constant exhaustion
  • Enlarged lymph nodes (armpits and neck)

This disease must be treated, so that in the future it does not lead to the development of serious neuropsychiatric diseases.

Diagnosis of chronic fatigue.

Often, chronic fatigue syndrome is difficult to diagnose due to the fact that most of the symptoms occur in other diseases. At the same time, the symptoms of this disease are manifested in a complex, and not one at a time. Only a specialist can make an accurate diagnosis after a detailed examination and a detailed medical history. Sometimes, in order to exclude other pathologies, the doctor may refer the patient to a blood or urine test. The main diagnostic sign of the disease is the occurrence of a persistent feeling of fatigue, which does not disappear after a good rest, and bad mood, loss of appetite, apathy, general weakness are concomitant factors. This condition can be supplemented by frequent colds, exacerbation of chronic diseases, which significantly reduces efficiency and exacerbates the feeling of constant fatigue.

Depending on the manifestation of the symptoms that provoked this disease, the patient can visit the following specialists:

  • Therapist
  • Psychologist
  • Neurologist
  • Endocrinologist
  • Immunologist

You can make an appointment with the specialists you are interested in in Moscow at the NCC Clinic No. 2 (Central Clinical Hospital of the Russian Academy of Sciences).

Treatment of chronic fatigue.

  • Medication (vitamins, immunomodulators, homeopathic, anti-inflammatory drugs, antidepressants, antivirals)
  • Physiotherapy (physiotherapy, acupuncture, soothing massage, hydrotherapy, etc. )
  • Recommended good sleep, diet, planned daily routine.

Disease prevention.

  • Proper nutrition
  • Rational daily routine planning
  • Sports activities
  • Healthy sleep
  • Refusal of bad habits.

If a situation arises in which a professional consultation of a neurologist becomes necessary, contact the specialists of the NCC No. 2 (CCH RAS). The best doctors of the capital will help you restore your health. Registration is available 24 hours a day on the website. You can also make an appointment with a neurologist by phone during working hours of the Central Clinical Hospital.

symptoms and treatment – Harmony of health

Chronic fatigue syndrome is a disease in which the human body experiences constant mental and physical weakness. Weakness occurs for unexplained reasons and may last for six months or more. People faced a similar ailment back in the 30s of the last century, but in fact, the diagnosis of chronic fatigue syndrome was first made only in 1988 year. Until that time, chronic fatigue was considered to be an accompanying symptom of various diseases, including infectious ones.

The feeling of extreme fatigue due to physical or mental overexertion has been experienced by many. As a rule, such a feeling arises after a responsible event or difficult work and disappears due to relaxation. In the case of ordinary overwork, a person is able to easily determine the cause of his fatigue and overcome it. With chronic fatigue syndrome, everything is different: the patient finds it difficult to remember when, why and under what circumstances he felt tired. This condition can deeply disturb and oppress the patient.

Modern medicine associates the appearance of chronic fatigue syndrome with a continuous acceleration of the pace of life and an increase in the flow of information. Any infectious disease can serve as an impetus for the onset of the disease. At the end of the acute period of infection, the patient may experience some weakness, fatigue and depression. Normally, this condition should pass in three weeks. With chronic fatigue syndrome, symptoms persist even after six months, and the patient has to turn to a medical center for professional help sooner or later.

Chronic fatigue syndrome: symptoms

The main symptom is endless fatigue that does not leave a person even after prolonged sleep and rest. Most patients develop a concomitant ailment – constant insomnia. Its appearance can be triggered by any factor – a change in the time zone, a change in work schedule, or banal stress.

Very often, chronic fatigue is accompanied by a significant deterioration in performance and attention, a sharp deterioration in the psycho-emotional state. Apathy, depression, hypochondria may develop. In some cases, against the background of chronic fatigue, phobias occur. There are cases of violation of thermoregulation and a sharp decrease in body weight.

With chronic fatigue syndrome, the patient often complains of dizziness, headaches, photophobia, dry eyes. Possible pharyngitis, tachycardia, soreness of the lymph nodes. Women may experience increased premenstrual syndrome.

Chronic fatigue syndrome: prevention

A healthy lifestyle is the surest way to avoid the development of the syndrome. Eat right, control the level of mental stress, do not forget about the benefits of adequate physical training. A person who adheres to the correct daily routine and knows how to avoid stressful situations is less susceptible to any diseases. Even if stress still overtakes you, allow yourself to relax and unwind.

Take at least short breaks while you work. If your work is associated with mental stress, do not be lazy to interrupt for simple physical exercises. Oddly enough, constant sitting is very tiring, so allowing the body to switch from mental work to physical work from time to time is very useful. No less useful for maintaining a healthy mental background is a change of scenery.