Amyotrophic Lateral Sclerosis

(ALS; Lou Gehrig's Disease; Motor Neuron Disease)


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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Causes    TOP

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

Risk Factors    TOP

Factors that may increase your chance of 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    TOP

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

Diagnosis    TOP

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.

Imaging tests may include:

Other tests may include:

  • Blood tests
  • Lumbar puncture to evaluate cerebrospinal fluid that surrounds the brain and spinal cord
  • Biopsy to evaluate tissue under a microscope

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.

Treatment    TOP

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:


The drug riluzole has been approved for ALS. The drug may slightly improve functioning, but it does not stop the disease from progressing.

Medications may include:

  • Muscle relaxants reduce spasticity
  • Nonsteroidal anti-inflammatory drugs (NSAIDs) and other pain medications
  • Atropine, scopolamine, botulinum toxin, antihistamine—To reduce heavy drooling
  • Antidepressants and anti-anxiety drugs
  • A combination of dextromethorphan and quinidine—to treat inappropriate laughter or crying

Other Types of Treatments

Supportive care may be needed as ALS progresses, including:

  • Physical therapy—To reduce pain associated with muscle cramping and spasticity.
  • Respiratory care—In some cases, you may need to receive a mixture of air and oxygen from a machine. A device may also be used that helps your breathing muscles contract. If you cannot move enough air in and out of your lungs, you may need surgery to have a tube inserted into your airway.
  • Nutritional care—Your doctor may make changes to your diet. In some cases, getting nutrition through tube feeding is needed.
  • Speech therapy—Speech therapy may be used to optimize communication. Therapy may include exploring alternate methods of communication.

Prevention    TOP

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


ALS Association
National Institute of Neurological Disorders and Stroke


ALS Society of British Columbia
ALS Society of Canada


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Last reviewed January 2015 by Rimas Lukas, MD
Last Updated: 9/3/2014

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