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Fatigue: Introduction

Fatigue is a general term for an abnormal condition in which a person feels a sensation of tiredness, weariness, exhaustion, weakness, or low energy. Fatigue is a symptom of a wide variety of mild to serious diseases, disorders and conditions. Fatigue can result from infection, inflammation, trauma, malignancy, chronic diseases, autoimmune diseases, mental illnesses and other abnormal processes.

Fatigue can occur in any age group or population, but it is particularly common in the elderly and in people with chronic diseases. Depending on the cause, the sensation of fatigue can be short-term and disappear quickly, such as when it occurs due to exercise or a single night of insomnia. Fatigue can also can be chronic and ongoing over a longer period of time, such as when it is due to depression or heart failure.

Fatigue can be the result of a wide variety of other conditions, diseases or disorders. These include anemia, hypotension, COPD, diabetes, chronic fatigue syndrome and Addison's disease. Causes also include influenza, dehydration, jet lag, depression, malnutrition, bacterial diseases, hypothyroidism, myasthenia gravis, viral infections, chronic pain, fever and pregnancy.

There are many symptoms that can accompany fatigue, depending on the disease, disorder or condition that is at the root of it. These include fever, weight loss, loss of appetite and dizziness. Fatigue, especially chronic fatigue, can seriously impact the ability to function effectively in everyday life. Underlying diseases, disorders or conditions of fatigue can also cause complications. For more details about symptoms and complications, see symptoms of fatigue.

Diagnosing fatigue and its root cause begins with taking a thorough personal and family medical history, including symptoms, and completing a physical examination, including a neurological examination. This may also include a mental health exam.

Making a diagnosis also includes performing a variety of other tests to help to diagnose the underlying disease, condition or disorder causing the fatigue.

Depending on the suspected cause, tests can include blood tests. A complete blood count (CBC) can help to determine if anemia or an infectious process, such as bacterial infection is present. A chemistry panel is a blood test that can test for dehydration or electrolyte imbalance, which can cause fatigue.

A blood glucose can check for diabetes. An urinanalysis can also help to diagnose dehydration and a variety of urinary tract conditions, which can cause fatigue. Liver function tests can evaluate liver health and a TSH and other thyroid tests can help to determine if hypothyroidism is the cause of fatigue.

Other tests may also be performed depending on the suspected cause. These include imaging tests, such as X-ray, CT scan, nuclear scans and MRI.

A diagnosis of fatigue and its cause can easily be delayed or missed because fatigue may be mild or not last for long periods of time. For information on misdiagnosis, refer to misdiagnosis of fatigue.

Treatment of fatigue involves diagnosing and treating the underlying disease, disorder or condition that is causing it. Some conditions can be easily and successfully treated and cured, while others may require more intensive treatment and may not have an optimal prognosis. For more information on treatment, refer to treatment of fatigue....more »

Fatigue: Fatigue means lacking energy or strength and is a very common symptom. However, the term in common usage may mean many things, including drowsiness (sleepiness), lethargy, tiredness, malaise, listlessness, or ...more »

Fatigue: Misdiagnosis

Diagnosing fatigue and its cause may be delayed or missed because the fatigue may not be severe or consistent enough for a person to seek medical care. IN addition, some people may believe that fatigue is a normal part of aging. Fatigue is a symptom of many different conditions, and some of them are potentially serious. A thorough medical evaluation is needed to ensure an accurate ...more misdiagnosis »

Causes of Fatigue:

The following medical conditions are some of the possible causes of Fatigue. There are likely to be other possible causes, so ask your doctor about your symptoms.

» Review Causes of Fatigue: Causes | Symptom Checker » | Assessment Questionnaire »

Common Causes of Fatigue

Home Diagnostic Testing and Fatigue

Home medical tests possibly related to Fatigue:

Causes of Types of Fatigue:

Review the causes of these more specific types of Fatigue:

Review causes of types of Fatigue in more specific categories:

Review causes of more specific types of Fatigue:

Fatigue: Symptom Checker

Listed below are some combinations of symptoms associated with Fatigue, as listed in our database. Visit the Symptom Checker, to add and remove symptoms and research your condition.

Symptom Checker

Symptom Checker

Fatigue Treatments

Treatment plans for fatigue are individualized depending on the cause, the presence of coexisting diseases, the age of the patient, and other factors. Treatment generally involves a multifaceted plan that addresses the underlying or associated cause and helps to minimize the fatigue so that a person can lead an active normal life.

Some common causes of fatigue, such as jet ...Fatigue Treatments

Some of the possible treatments listed in sources for treatment of Fatigue may include:

  • Adequate rest
  • Moderate activity
  • No exercise
  • Diet supplementation
  • Vitamin supplementation
  • Antibiotics to treat underlying infection
  • more treatments...»

Review further information on Fatigue Treatments.

Alternative Treatments for Fatigue

Alternative treatments or home remedies that have been listed as possibly helpful for Fatigue may include:

Stories from Users for Fatigue

Real-life user stories relating to Fatigue:

Message Boards for Fatigue

Symptom specific forums: The following patient stories in our interactive forums and message boards relate to Fatigue or relevant symptoms:

Diagnostic tests for Fatigue:

Various tests are used in the diagnosis of Fatigue. Some of these are listed below :

  • ( should be selected judiciously)
  • Physical examination
    • Blood pressure taken when lying down and again after rapidly arising to standing position ( looking for postural hypotension of Addison's disease)
    • Feel lymph nodes for enlargement
    • Abdominal examination looking for an enlarged liver or spleen
    • Full nervous system examination. If abnormalities are found may suggest muscular dystrophy, motor neurone disease or Parkinson's disease, Multiple sclerosis
    • Examine for mild signs of chronic fatigue syndrome including muscle tenderness, mild red pharynx and tender slightly enlarged neck lymph nodes
  • more tests...»

Fatigue: Animations

Medications or substances causing Fatigue:

The following drugs, medications, substances or toxins are some of the possible causes of Fatigue as a symptom. Always advise your doctor of any medications or treatments you are using, including prescription, over-the-counter, supplements, herbal or alternative treatments.

Drug interactions causing Fatigue:

When combined, certain drugs, medications, substances or toxins may react causing Fatigue as a symptom. Always advise your doctor of any medications or treatments you are using, including prescription, over-the-counter, supplements, herbal or alternative treatments.

  • Meprobamate and alcohol interaction
  • Equanil and alcohol interaction
  • Meprospan and alcohol interaction
  • Miltown and alcohol interaction
  • Probate and alcohol interaction
  • Trancot and alcohol interaction
  • more interactions...»

Fatigue: Comorbid Symptoms

Some of the comorbid or associated medical symptoms for Fatigue may include these symptoms:

Causes of General Symptom Types

Research the causes of these more general types of symptom:

Causes of Similar Symptoms to Fatigue

Research the causes of these symptoms that are similar to, or related to, the symptom Fatigue:

Assessment Questionnaire: Questions your doctor may ask (and why!)

During a consultation, your doctor will use various techniques to assess the symptom: Fatigue. These will include a physical examination and possibly diagnostic tests. (Note: A physical exam is always done, diagnostic tests may or may not be performed depending on the suspected condition) Your doctor will ask several questions when assessing your condition. It is important to openly share any pertinent information to help your doctor make an accurate diagnosis.

It is also very important to bring an up-to-date list of all of your all medical conditions, medications including dosages, and names of numbers of any specialist you see.

Create your printable checklist here.

See Fatigue Assessment Questionnaire (32 listings)

Fatigue: Deaths

Read more about causes and Fatigue deaths.

Misdiagnosis and Fatigue

Unnecessary hysterectomies due to undiagnosed bleeding disorder in women: The bleeding disorder called Von Willebrand's disease is quite common in women, but often fails to be correctly diagnosed. Women with the condition tend more »

Anemia undiagnosed in pregnancy: The onset of anemia (low red blood cells) in pregnancy is sometimes overlooked, despite it being a well-known complication of pregnancy. The problem may be that the more »

Underactive thryoid may be misdiagnosed as depression: Hypothyroidism, or underactive thyroid, is an endocrine gland disorder that is more common in women. It more »

Cluster of diseases with difficult diagnosis issues: There is a well-known list of medical conditions that are all somewhat difficult to diagnose, and all can present in a variety of different severities. Diseases more »

RLS sleep disorder causing night-time leg sensations often misdiagnosed: A common but relatively unknown sleep-related disorder called Restless Leg Syndrome (RLS) is often misdiagnosed. The typical symptoms are night-time tingling, crawling, or more »

Pituitary conditions often undiagnosed cause of symptoms: There are a variety of symptoms that can be caused by a pituitary disorder (see symptoms of pituitary disorders). For example, fatigue, headache, weight gain, more »

Vitamin B12 deficiency under-diagnosed: The condition of Vitamin B12 deficiency is a possible misdiagnosis of various conditions, such as more »

Fatigue: Research Related Doctors & Specialists

Other ways to find a doctor, or use doctor, physician and specialist online research services:

Fatigue: Undiagnosed Conditions

Conditions that are commonly undiagnosed in related areas may include:

Definitions of Fatigue:

Fatigue is that state, following a period of mental or bodily activity, characterized by a lessened capacity for work and reduced efficiency of accomplishment, usually accompanied by a feeling of weariness, sleepiness, or irritability. (On-line Medical Dictionary)
- (Source - Diseases Database)

State of weariness following a period of exertion, mental or physical, characterized by a decreased capacity for work and reduced efficiency to respond to stimuli.
- (Source - CRISP)

A condition marked by extreme tiredness and inability to function due lack of energy. Fatigue may be acute or chronic.
- (Source - National Cancer Institute)

Organs affected by Fatigue:

The list of organs typically affected by Fatigue may include, but is not limited to:

  • General constitution

Detailed list of causes of Fatigue

The list below shows some of the causes of Fatigue mentioned in various sources:

How Common are these Causes of Fatigue?

This information refers to the general prevalence and incidence of these diseases, not to how likely they are to be the actual cause of Fatigue. Of the 3235 causes of Fatigue that we have listed, we have the following prevalence/incidence information:

  • 38 causes are "very common" diseases
  • 42 causes are "common" diseases
  • 25 causes are "uncommon" diseases
  • 4 causes are "rare" diseases
  • 104 causes are "very rare" diseases
  • 3114 causes have no prevalence information.

Conditions listing medical symptoms: Fatigue:

The following list of conditions have 'Fatigue' or similar listed as a symptom in our database. This computer-generated list may be inaccurate or incomplete. Always seek prompt professional medical advice about the cause of any symptom.

Select from the following alphabetical view of conditions which include a symptom of Fatigue or choose View All.

View All A B C D E F G H I J K L M N O P Q R S T U V W X Y Z #





Conditions listing medical complications: Fatigue:

The following list of medical conditions have Fatigue or similar listed as a medical complication in our database. The distinction between a symptom and complication is not always clear, and conditions mentioning this symptom as a complication may also be relevant. This computer-generated list may be inaccurate or incomplete. Always seek prompt professional medical advice about the cause of any symptom.







  • Lyme disease ... persistent fatigue, severe fatigue, severe fatigue








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Causes of Fatigue Based on Risk Factors

This information shows analysis of the list of causes of Fatigue based on whether certain risk factors apply to the patient:

  • Travel - has the patient travelled recently?
  • Diabetes - history of diabetes or family history of diabetes?

    Doctors and specialists: Who should I consult about Fatigue?

    Depending on the seriousness of the onset of Fatigue, you may want to consult one of the following medical professionals.

    Important:In extreme cases, always seek advice from emergency services :

    What are the alternative names for Fatigue:

    Lack of energy, TATT, Tired all the time
    - (Source - Diseases Database)

    Classifications of Fatigue:

    Subtypes of Fatigue:

    Drowsiness (1139 causes), Malaise (468 causes), Lethargy (399 causes), Chronic fatigue syndrome (3 causes), Severe fatigue (5 causes), Extreme fatigue (105 causes), Lack of energy (52 causes), Yawning Excessively (20 causes), Sedative effect, Yawning (18 causes), Daytime drowsiness (25 causes), Daytime tiredness (18 causes), General discomfort (5 causes), Feeling under the weather (9 causes), Constant eye fatigue (8 causes), Daytime drowsiness in children (19 causes), Daytime drowsiness in pregnancy (30 causes), Daytime tiredness in pregnancy (30 causes), Drowsiness in pregnancy (30 causes), Easily fatigued (57 causes), Episodic severe fatigue (23 causes), Excessive yawning (8 causes), Excessive yawning in children (7 causes), Excessively sleepy (17 causes), Extreme fatigue in pregnancy (30 causes), Extreme tiredness (31 causes), Extreme tiredness in pregnancy (30 causes), Eye fatigue (8 causes), Eye fatigue in both eyes (4 causes), Eye fatigue in one eye (8 causes), Fatigue in children (39 causes), Fatigue in pregnancy (30 causes), Fatigue worsened by exercise (12 causes), Yawning excessively in pregnancy (9 causes), Lethargy in pregnancy (24 causes), Listlessness (33 causes), Listlessness in pregnancy (30 causes), Cachexia (64 causes), Sports related Fibromyalgia (5 causes), Tiredness (669 causes), Tiredness in pregnancy (30 causes), Weak, tired and apprehensive (28 causes)

    Medical Conditions associated with Fatigue:

    Common symptoms (8589 causes), Sick (5751 causes), Muscle weakness (4300 causes), Muscle symptoms (7251 causes), Weakness (3752 causes), Energy symptoms (3108 causes), Pain (6458 causes), Movement symptoms (6001 causes), Sensations (6520 causes), Brain symptoms (2787 causes), Neurological symptoms (9575 causes), Sensory symptoms (7134 causes), Nerve symptoms (9132 causes), Musculoskeletal symptoms (6264 causes), Body symptoms (5672 causes), Head symptoms (10192 causes)

    Symptoms related to Fatigue:

    Malaise (468 causes), Drowsiness (1139 causes), Prostration (65 causes), Listlessness (33 causes), Weakness (3752 causes), Tired (669 causes), Lethargy (399 causes), Muscle weakness (4300 causes), Sleepiness (1139 causes), Fever (2274 causes), Recurring fever, Chronic fatigue, Tiredness (669 causes), Anemia (926 causes), Hemochromatosis, Addison's disease

    Medical articles on signs and symptoms:

    Doctor-patient articles related to symptoms and diagnosis:

    These general medical articles may be of interest:

    Medical News summaries about Fatigue

    Our news pages contain the following medical news summaries about Fatigue and many other medical conditions:

    Related medical articles from our Disease Center for Fatigue:

    More Ways To Research Medical Signs and Symptoms:


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