Services & Conditions
Amyotrophic Lateral Sclerosis (ALS)

Amyotrophic Lateral Sclerosis (ALS)


Amyotrophic lateral sclerosis (ALS) is a nervous system disorder that steadily worsens over time. It affects nerves in the brain and spine that are responsible for muscle movement. The nerves gradually die which can lead to almost total paralysis, including being unable to breathe. ALS is fatal, often due to respiratory failure.

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

The symptoms of ALS are caused by the death of the nerves. If the nerves can not send signals to the muscle they are not able to work. Overtime the muscles become weak and shrink from disuse.

Risk Factors

Factors that may increase your chance of ALS include:

  • Having a family member with ALS
  • Having certain genetic mutations

Military veterans have twice the risk of ALS as the general population. It is not clear why.


The first signs of ALS are subtle and can be different from person to person. They may include:

  • Changes in how you speak
  • Frequent tripping while walking or general clumsiness
  • Trouble with fine motor tasks like grasping a pen

The speed of the progression can be very different between people. As the disease progresses it can lead to:

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


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

Imaging tests to look for changes in the brain or spine may include:

  • MRI scan
  • CT scan

Other tests may include:

  • Blood tests—to look for infections or metabolic change
  • Lumbar puncture—to look for changes in the fluid that surrounds the brain and spinal cord
  • Biopsy to evaluate tissue under a microscope

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

Your thinking and processing skills may also be checked.


There is currently no cure for ALS. A combination of treatments may help to reduce or manage symptoms. Treatment options include:


There are no current guidelines to prevent ALS because the cause is unknown.


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