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

Prognosis is poor in most cases because of the progressive nature of the condition due to eventual respiratory failure. After diagnosis is made, lifespan ranges from 2-5 years. The 5 year survival rate is 25% and up to 10% of patients will survive more than 10 years. In general, the younger the age of onset, the slower the disease progresses.

The Nervous System

Nucleus factsheet image
© 2009 Nucleus Medical Art, Inc.


The cause of ALS is not known, but it appears that genes may play a role in a very small number of cases. Also, research has shown that there may be a reduced response to cell stress, as well as cell toxicity, related to certain protein build-up in the brain.

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition. Risk factors include:

  • Having a family member with ALS
  • Military personnel may have an increased risk
  • Persons with certain genetic mutations


Symptoms include:

  • Progressive weakness in arms and legs (at first often on only one side) over weeks to months without changes in sensory abilities.
  • Initial presentation may be a wrist or foot drop
  • Trouble holding things without dropping them
  • Frequent tripping while walking
  • Shrunken muscles
  • Twitchy muscles
  • Unpredictable changing emotions
  • Clumsiness
  • Overactive reflexes
  • Slurred speech
  • Hoarseness
  • Trouble chewing and swallowing, resulting in frequent choking and gagging
  • Weight loss due to trouble eating
  • Trouble breathing
  • Excess salivation, drooling
  • Cognition is intact
  • Sensation is intact
  • Trouble coughing, resulting in development of pneumonia]]>



The doctor will ask about your symptoms and medical history, and perform a physical exam. There are no tests that definitively diagnose ALS, but tests may be used to rule out other medical conditions.

Tests may include:

  • Electromyogram (EMG)]]> —to look for progressive muscle weakness and twitching
  • ]]>CT Scan]]> —a type of x-ray that uses a computer to make pictures of the structures inside the head
  • ]]>MRI Scan]]> —a test that uses magnetic waves to make pictures of the structures inside the head
  • Blood tests—to rule out metabolic, heavy metal exposure, or rarely infections such as ]]>lyme]]> disease or ]]>HIV]]>
  • ]]>Lumbar puncture]]> —a procedure to collect cerebrospinal fluid (CSF)
  • Urine tests



There is currently no cure for ALS.

For you and your family, a multidisciplinary approach may work best. This approach may include:

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

Treatments options include:


The drug, called riluzole]]> , has been approved for ALS with a clinical trial revealing a modest lengthening of survival. The drug may slightly improve functioning, but it doesn't stop the disease from progressing. A study, though, showed that the addition of ]]>lithium carbonate]]> (a medication used to treat mood disorders) to riluzole may slow the progression of ALS and prolong survival. ]]>]]> Other drugs are also being studied.

Your doctor may prescribe these medications for symptom

  • ]]>Diazepam]]> (eg, Valium), ]]>baclofen]]> (eg, Lioresal), or ]]>dantrolene]]> —to reduce spasticity
  • Nonsteroidal anti-inflammatory drugs (NSAIDs) and other pain medications
  • ]]>Atropine]]> (eg, AtroPen), ]]>scopolamine]]> (eg, Isopto), or antihistamine—to reduce heavy drooling
  • Antidepressants and anti-anxiety medications

Other Types of Treatments

  • Physical therapy—This is used 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. 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 can include exploring alternative methods of communication.


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