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Muscle weakness

Muscle weakness: Introduction

Muscle weakness is a symptom of a wide variety of mild to serious diseases, disorders and conditions. Muscle weakness can result from infection, trauma, malignancy, autoimmune diseases, and other abnormal processes.

Muscle weakness can occur in any age group or population and can affect the whole body or only a portion of the body. Temporary muscle weakness can result from a relatively mild condition, such as remaining sedentary for a short period of time. Muscle weakness can be the result of a moderate traumatic condition, disorder or disease, such as strained muscle or torn muscle. Muscle weakness can also accompany serious conditions that can even be life-threatening. These include severe dehydration, spinal cord injury, stroke.

Muscle weakness can occur suddenly and severely, such as that which happens with a torn muscle or Bell's palsy. Muscle weakness can also be chronic and ongoing over a long period of time, such as when muscle weakness is due to the complications of stroke or cerebral palsy.

Muscle weakness can be the result of a neurologic diseases, disorders or conditions, which affect the nervous system. These include cerebral palsy, prolapsed disc in the back, stroke, Guillain-Barre syndrome and multiple sclerosis. Myasthenia gravis is an autoimmune disease that affects nerve function and results in muscle weakness.

Muscle weakness can be the result of a muscular diseases, disorders or conditions, which affect the ability of the muscles to move. These include muscular dystrophy and myotonic dystrophy.

Metabolic diseases can also cause muscle weakness. These include electrolyte imbalance, Addison's disease and hyperparathyroidism.

Muscle weakness can also be caused by dehydration, bed rest, muscle trauma, anemia, malnutrition, and some viral infections and bacterial infections, such as viral poliomyelitis and bacterial or viral food poisoning.

Muscle weakness often occurs in conjunction with other symptoms, which vary depending on the underlying disease, disorder or condition. Other symptoms can include pain or paresthesia, fever, and flu-like symptoms. Complications of muscle weakness include muscle atrophy and contractures. Other complications vary depending on the underlying cause. For more details about symptoms and complications, see symptoms of muscle weakness.

Diagnosing muscle weakness and its root cause begins with taking a thorough personal and family medical history, including symptoms, and completing a physical examination and a through neurological exam. This includes a thorough assessment of the muscle weakness by asking about a variety of factors. These include when, how often and how long the weakness has been experienced. Other questions include what part of the body is involved and factors that seem to make the weakness worse and make it better. Questions are also asked about how severe the muscle weakness is, how it impacts daily life and any accompanying symptoms.

Making a diagnosis also includes performing a variety of tests to help to diagnose potential underlying diseases, conditions or disorders. Tests can include blood tests, lumbar puncture, urinalysis, and imaging tests, such as X-ray, CT scan, nuclear scans, and MRI.

Tests may also include an electromyography (EMG) which tests the electrical activity of muscles. A nerve conduction test may also be ordered to measure the ability of nerves to send electrical signals. These tests can help to diagnose nerve entrapment or a pinched nerve.

A diagnosis of muscle weakness and its cause can easily be delayed or missed because muscle weakness may be mild and for other reasons. For information on misdiagnosis, refer to misdiagnosis of muscle weakness.

Treatment of muscle weakness involves diagnosing and treating the underlying disease, disorder or condition that is causing it. Some conditions can be 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 muscle weakness....more »

Muscle weakness: Misdiagnosis

Diagnosing muscle weakness and its cause may be delayed or missed because in some cases, muscle weakness may not be severe enough for a person to seek medical care. Muscle weakness may also progress slowly or occur intermittently, also delaying a diagnosis. A diagnosis may also be delayed because a person may assume that muscle weakness is a normal part of the aging process.

Muscle weakness is ...more misdiagnosis »

Causes of Muscle weakness:

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

» Review Causes of Muscle weakness: Causes | Symptom Checker » | Assessment Questionnaire »

Home Diagnostic Testing and Muscle weakness

Home medical tests possibly related to Muscle weakness:

Causes of Types of Muscle weakness:

Review the causes of these more specific types of Muscle weakness:

Review causes of types of Muscle weakness in more specific categories:

Review causes of more specific types of Muscle weakness:

Muscle weakness: Symptom Checker

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

Symptom Checker

Symptom Checker

Muscle weakness Treatments

Treatment plans for muscle weakness are individualized depending on the underlying cause, the presence of coexisting diseases, the age and medical history of the patient, the severity of muscle weakness and other factors. Treatment generally involves a multifaceted plan that addresses the cause, helps to build strength, decreases the risk of developing complications, such as muscle ...Muscle weakness Treatments

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

  • Magnesium - possibly used for related magnesium deficiency
  • Potassium - possibly used for related potassium deficiency
  • Vitamin B12 - possibly used for related vitamin B12 deficiency
  • Phosphorus - possibly used for related phosphorus deficiency
  • Collagenase - mainly used to treat muscle weakness in patients with myasthenia gravis
  • Santyl - mainly used to treat muscle weakness in patients with myasthenia gravis
  • more treatments...»

Review further information on Muscle weakness Treatments.

Stories from Users for Muscle weakness

Real-life user stories relating to Muscle weakness:

Message Boards for Muscle weakness

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

Diagnostic tests for Muscle weakness:

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

  • General appearance
    • Inspect gait
    • Looking for bruising, deformity of arm or leg, swelling of the arm or leg, abnormal posture of body
    • General inspection of the entire body musculature with the person undressed. Compare one side with the other for wasting and try to work out which muscle groups are involved (proximal, distal or generalized, symmetrical or asymmetrical). Muscle wasting may indicate a primary muscle disease, wasting due to disuse or disease of the nerve supplying the muscle
  • Physical examination
    • Blood pressure and pulse to detect risk factors for stroke. Blood pressure is increased in Conn's syndrome and Cushing's syndrome which may both cause muscle weakness
    • Listen for carotid bruits which can indicate narrowing of arteries to brain and thus an increased risk of stroke
  • more tests...»

Muscle weakness: Animations

Medications or substances causing Muscle weakness:

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

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

  • Methyldopa and lithium interaction
  • Aldomet and lithium interaction
  • Amodopa and lithium interaction
  • Lithium (Eskalith) and ACE Inhibitor interaction
  • Lithium (Eskalith) and Angiotensin Receptor Blocker (ARBs) interaction
  • Lithium (Eskalith) and COX-2 Inhibitor interaction
  • Lithium (Eskalith) and NSAID interaction
  • more interactions...»

Muscle weakness: Comorbid Symptoms

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

Causes of General Symptom Types

Research the causes of these more general types of symptom:

Research the causes of related medical symptoms such as:

Causes of Similar Symptoms to Muscle weakness

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

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

During a consultation, your doctor will use various techniques to assess the symptom: Muscle weakness. 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 Muscle weakness Assessment Questionnaire (31 listings)

Muscle weakness: Deaths

Read more about causes and Muscle weakness deaths.

Misdiagnosis and Muscle weakness

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, 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, diabetes-like symptoms, more »

Muscle weakness: Research Related Doctors & Specialists

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

Muscle weakness: Undiagnosed Conditions

Conditions that are commonly undiagnosed in related areas may include:

Causes of Muscle weakness listed in Disease Database:

Other medical conditions listed in the Disease Database as possible causes of Muscle weakness as a symptom include:

Definitions of Muscle weakness:

A vague complaint of debility, fatigue, or exhaustion attributable to weakness of various muscles. The weakness can be characterized as subacute or chronic, often progressive, and is a manifestation of many muscle and neuromuscular diseases. (From Wyngaarden et al., Cecil Textbook of Medicine, 19th ed, p2251)
- (Source - Diseases Database)

Organs affected by Muscle weakness:

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

Detailed list of causes of Muscle weakness

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

How Common are these Causes of Muscle weakness?

This information refers to the general prevalence and incidence of these diseases, not to how likely they are to be the actual cause of Muscle weakness. Of the 4300 causes of Muscle weakness that we have listed, we have the following prevalence/incidence information:

  • 33 causes are "very common" diseases
  • 34 causes are "common" diseases
  • 19 causes are "uncommon" diseases
  • 21 causes are "rare" diseases
  • 115 causes are "very rare" diseases
  • 4164 causes have no prevalence information.

Conditions listing medical symptoms: Muscle weakness:

The following list of conditions have 'Muscle weakness' 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 Muscle weakness 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: Muscle weakness:

The following list of medical conditions have Muscle weakness 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 Muscle weakness Based on Risk Factors

This information shows analysis of the list of causes of Muscle weakness 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 Muscle weakness?

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

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

    Classifications of Muscle weakness:

    Subtypes of Muscle weakness:

    Fatigue (3235 causes), Floppy baby (33 causes), Proximal muscle weakness (45 causes), Reduced muscle tone (683 causes), Severe fatigue (5 causes), Drowsiness (1139 causes), Lethargy (399 causes), Malaise (468 causes), Extreme fatigue (105 causes), Lack of energy (52 causes), Chronic fatigue syndrome (3 causes), Rhabdomyolysis (67 causes), Feeling under the weather (9 causes), General discomfort (5 causes), Excessive yawning (8 causes), Daytime drowsiness in children (19 causes), Yawning excessively in pregnancy (9 causes), Excessively sleepy (17 causes), Fatigue in pregnancy (30 causes), Listlessness (33 causes), Eye fatigue in one eye (8 causes), Sedative effect, Lethargy in pregnancy (24 causes), Excessive yawning in children (7 causes), Daytime drowsiness in pregnancy (30 causes), Weak, tired and apprehensive (28 causes), Drowsiness in pregnancy (30 causes), Extreme tiredness in pregnancy (30 causes), Cachexia (64 causes), Eye fatigue (8 causes), Extreme fatigue in pregnancy (30 causes), Yawning (18 causes), Listlessness in pregnancy (30 causes), Eye fatigue in both eyes (4 causes), Daytime tiredness (18 causes), Tiredness (669 causes), Fatigue worsened by exercise (12 causes), Easily fatigued (57 causes), Constant eye fatigue (8 causes), Episodic severe fatigue (23 causes), Yawning Excessively (20 causes), Sports related Fibromyalgia (5 causes), Daytime drowsiness (25 causes), Fatigue in children (39 causes), Daytime tiredness in pregnancy (30 causes), Tiredness in pregnancy (30 causes), Extreme tiredness (31 causes)

    Medical Conditions associated with Muscle weakness:

    Muscle symptoms (7251 causes), Weakness (3752 causes), Sick (5751 causes), Musculoskeletal symptoms (6264 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), Common symptoms (8589 causes), Body symptoms (5672 causes), Head symptoms (10192 causes)

    Symptoms related to Muscle weakness:

    Paralysis (325 causes), Seizure (2418 causes), Muscle spasm (29 causes), Muscle pain (956 causes), Muscle cramps (283 causes), Weakness (3752 causes), Muscular dystrophy, Duchenne muscular dystrophy, Becker muscular dystrophy, Diabetes (212 causes), Cushing's syndrome (28 causes), Anemia (926 causes), Thyroid disease (18 causes), Hyperthyroidism (41 causes), Hypothyroidism (106 causes), Nerve disorders, Lupus (14 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 Muscle weakness

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

    Evidence Based Medicine Research for Muscle weakness

    Medical research papers related to Muscle weakness include:

    Research More Evidence-Based Medicine at

    Related medical articles from our Disease Center for Muscle weakness:

    More Ways To Research Medical Signs and Symptoms:


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