Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a progressive nervous system disorder. It gradually destroys the nerves responsible for muscle movement. Over time, ALS leads to almost total paralysis of muscle movement, including breathing. Eventually, the disorder leads to respiratory failure.

  • Causes

    The cause of ALS is unknown. Genes may play a role.

  • Definition

    Amyotrophic lateral sclerosis (ALS) is a progressive nervous system disorder. It gradually destroys the nerves responsible for muscle movement. Over time, ALS leads to almost total paralysis of muscle movement, including breathing. Eventually, the disorder leads to respiratory failure.

    The Nervous System
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  • Diagnosis

    You will be asked about your symptoms and medical history. A physical exam will be done. There are no tests that can diagnose ALS. Tests may be used to rule out other medical conditions.

    Images may be taken of your bodily structures. This can be done with:

    • CT scan
    • MRI

    Your bodily fluids and tissues may be tested. This can be done with:

    • Blood tests
    • Lumbar puncture
    • Biopsy


    Your muscles and nerves may be evaluated. This can be done with
    electromyogram
    (EMG)/nerve conduction velocities (NCV).

    Your cognitive skills may be assessed. This can be done with neuropsychological testing.

  • Prevention

    There are no guidelines for preventing ALS because the cause is unknown.

  • Risk Factors

    Factors that may increase your risk of getting ALS include:

    • Having a family member with ALS
    • Being in the military or having other occupations with risk of exposure
    • Having certain genetic mutations

  • Symptoms

    Symptoms of ALS include:

    • Progressive weakness in arms and legs
    • Wrist or foot drop
    • Difficulty holding things
    • Frequent tripping while walking
    • Muscle twitching
    • Unpredictable and changing emotions
    • Slurred speech
    • Hoarseness and coughing
    • Trouble chewing and swallowing, resulting in frequent choking and gagging
    • Weight loss due to trouble eating
    • Trouble breathing
    • Excess salivation, drooling

  • Treatment

    There is currently no cure for ALS.

    Treatment may help to reduce or manage symptoms.
    A combination of treatments may work best. This may include:

    • Taking medications

    • Working with therapists and joining a
      support group
    • Participating in social activities

    Treatment options include: