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Lethargy: Introduction

Lethargy is a fairly imprecise description of the feeling or slowness, sluggishness, tiredness, or lack of energy. Lethargy in common usage may mean many things, including fatigue, drowsiness (sleepiness), lethargy, tiredness, malaise, listlessness, or weakness (including muscular weakness). The causes of these other similar symptoms also need to be investigated in researching a symptom of lethargy. Nevertheless, any type of lethargy symptom can indicate a serious medical condition and needs prompt medical investigation....more »

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

Causes of Lethargy:

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

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

Common Causes of Lethargy

Home Diagnostic Testing and Lethargy

Home medical tests possibly related to Lethargy:

Causes of Types of Lethargy:

Review causes of types of Lethargy in more specific categories:

Review causes of more specific types of Lethargy:

Lethargy: Symptom Checker

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

Symptom Checker

Symptom Checker

Lethargy Treatments

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

Review further information on Lethargy Treatments.

Stories from Users for Lethargy

Real-life user stories relating to Lethargy:

Message Boards for Lethargy

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

Diagnostic tests for Lethargy:

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

  • Tests 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...»

Lethargy: Animations

Medications or substances causing Lethargy:

The following drugs, medications, substances or toxins are some of the possible causes of Lethargy 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 Lethargy:

When combined, certain drugs, medications, substances or toxins may react causing Lethargy 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.

  • Acyclovir and Zovirax interaction
  • Trizivir and acyclovir interaction
  • Lanoxin (Digoxin) and Cardioquin (Quinidine) interaction
  • Lanoxin (Digoxin) and Quinaglute (Quinidine) interaction
  • Lanoxin (Digoxin) and Quinidex (Quinidine) interaction
  • more interactions...»

Lethargy: Comorbid Symptoms

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

Causes of General Symptom Types

Research the causes of these more general types of symptom:

Causes of Similar Symptoms to Lethargy

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

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

During a consultation, your doctor will use various techniques to assess the symptom: Lethargy. 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 Lethargy Assessment Questionnaire (32 listings)

Lethargy: Deaths

Read more about causes and Lethargy deaths.

Misdiagnosis and Lethargy

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 in this group include multiple sclerosis, lupus, 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, 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 »

Lethargy: Research Related Doctors & Specialists

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

Lethargy: Undiagnosed Conditions

Conditions that are commonly undiagnosed in related areas may include:

Organs affected by Lethargy:

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

  • General constitution

Detailed list of causes of Lethargy

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

How Common are these Causes of Lethargy?

This information refers to the general prevalence and incidence of these diseases, not to how likely they are to be the actual cause of Lethargy. Of the 399 causes of Lethargy that we have listed, we have the following prevalence/incidence information:

  • 9 causes are "very common" diseases
  • 8 causes are "common" diseases
  • 4 causes are "uncommon" diseases
  • 0 causes are "rare" diseases
  • 18 causes are "very rare" diseases
  • 381 causes have no prevalence information.

Conditions listing medical symptoms: Lethargy:

The following list of conditions have 'Lethargy' 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 Lethargy or choose View All.

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


























Conditions listing medical complications: Lethargy:

The following list of medical conditions have Lethargy 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.



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Causes of Lethargy Based on Risk Factors

This information shows analysis of the list of causes of Lethargy 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 Lethargy?

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

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

    Classifications of Lethargy:

    Medical Conditions associated with Lethargy:

    Fatigue (3235 causes), Muscle weakness (4300 causes), Common symptoms (8589 causes), Sick (5751 causes), Fatigue symptoms (3235 causes), Energy symptoms (3108 causes), Pain (6458 causes), Movement symptoms (6001 causes), Weakness (3752 causes), Sensations (6520 causes), Brain symptoms (2787 causes), Neurological symptoms (9575 causes), Sensory symptoms (7134 causes), Muscle symptoms (7251 causes), Nerve symptoms (9132 causes), Musculoskeletal symptoms (6264 causes), Body symptoms (5672 causes), Head symptoms (10192 causes)

    Symptoms related to Lethargy:

    Fatigue (3235 causes), Malaise (468 causes), Drowsiness (1139 causes), Prostration (65 causes), Listlessness (33 causes), Weakness (3752 causes), Tired (669 causes), Sleepiness (1139 causes), Insomnia (521 causes), Chronic fatigue syndrome (3 causes), Depression (629 causes), Dementia (394 causes), Renal failure (115 causes), Cirrhosis of liver (119 causes), Temporal lobe abscess, Alzheimer's disease (2 causes), Cocaine abuse (2 causes), Carbon monoxide poisoning, Huntington's disease (2 causes)

    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 Lethargy

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

    More Ways To Research Medical Signs and Symptoms:


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