What Is ALS?

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Amyotrophic lateral sclerosis (ALS), also called "Lou Gehrig's disease," is a progressive and ultimately fatal neurodegenerative disease that affects the nerves that control movement. ALS leads to people becoming so weak that they are paralyzed, and half of the people impacted will die within two to five years.

The causes are unknown, but some combination of genetics and environmental exposures may be to blame. There is no cure for ALS, but there are some treatments that may slow the loss of physical function and improve the quality of life for people impacted by it.

Ways to Improve Life Expectancy with Lou Gehrig’s Disease
Verywell / Melissa Ling

What Is ALS?

ALS is a neurodegenerative disease that affects motor neurons, which are the nerve cells that control the movement of muscles.

"Upper motor neurons" originate in the brain. "Lower motor neurons" originate in the spinal cord. ALS destroys both upper and lower motor neurons, but a person often starts with symptoms of either upper or lower motor neuron disease.

When upper motor neurons are impacted, the result is muscle stiffness ("spasticity"). When lower motor neurons are impacted, the result is muscle weakness, loss of muscle ("atrophy"), and twitching ("fasciculations").

ALS is medically classified by which motor neurons are impacted:

  • Classical ALS is characterized by a deterioration of upper and lower motor neurons. This type of ALS affects more than two-thirds of those with the disease.
  • Primary lateral sclerosis (PLS) is characterized by deterioration of the upper motor neurons. If the lower motor neurons are not impacted within two years, the disease usually remains a pure upper motor neuron disease. This is the rarest form of ALS.
  • Progressive bulbar palsy (PBP) starts with difficulties in speaking, chewing, and swallowing due to lower motor neuron deterioration. This disorder affects about 25% of those with ALS.
  • Progressive muscular atrophy (PMA) is characterized by deterioration of the lower motor neurons. If the upper motor neurons are unaffected within two years, the disease usually remains a purely lower motor neuron disease.


Unfortunately, the prognosis for ALS is poor. ALS is progressive, and it is terminal within five years for 80% of the people impacted by it.

As ALS progresses, people are unable to move their arms and legs to walk or get out of bed, and they may lose the ability to talk, eat, and breathe on their own.


Complications can arise from the neurological damage of the disease process or from treatments:

  • Choking, due to impaired swallowing
  • Shortness of breath, due to the atrophy of breathing muscles
  • Risk of falling, due to weakness and atrophy of the muscles
  • Nutritional deficiencies, due to trouble eating
  • Infections, from medical devices like ventilators, feeding tubes, and urinary catheters
  • Anxiety and depression, related to an unpredictable and terminal illness
  • Inappropriate emotional outbursts, related to damage to that part of the brain
  • Cognitive changes and dementia

Life Expectancy

According to the ALS Association, the average life expectancy of a person with ALS is three years. However, it varies greatly:

  • 20% live five years or more.
  • 10% live 10 or more years.
  • 5% will live for more than 20 years.

How ALS Causes Death

Death from ALS is usually caused by respiratory failure, due to the muscles that allow for breathing becoming paralyzed. Both non-invasive and invasive ventilation can ease breathing, but ALS will continue to progress.


While there is no cure for ALS or ways to stop the progression of the disease completely, there are some treatments that may improve life expectancy and quality of life. These include:


Rilutek (riluzole) has been in use since 1995 and has been shown in randomized double-blind clinical trials to prolong life expectancy for approximately two to three months, but it did not relieve symptoms. This medication also goes by the name of Tiglutek when in a liquid form and Exservan when used as an oral film, both of which are easier for people with problems swallowing.

Radicava (edaravone) is a free-radical scavenger medication that was approved in 2017. In the phase 3 trial that led to its licensure, it lessened the decline in physical functioning by 33% in a very select group of people who were in the study. However, researchers caution that those results may not be generalizable to everyone with ALS.

Nuedexta (dextromethorphan hydrobromide/quinidine sulfate) may help improve bulbar motor function (important for speech and swallowing). In particular, it may help to better speech control with fewer pauses, but more study is needed.

Noninvasive Ventilation

The use of noninvasive ventilation (NIV) is a cornerstone of ALS treatment. The primary mode of NIV is positive-pressure ventilation, which is basically breathing through a mask that fits over the mouth and nose.

Ultimately, more invasive ventilation through a breathing tube down the throat or via a hole in the front of the neck (tracheostomy) may become necessary.

Because ventilation ultimately becomes a life-support technology in ALS patients, it can interfere with the ability to die naturally. People with ALS may want to decide at the outset when to withdraw mechanical ventilation, while they have the physical and mental capacity to craft advance directives.

Diaphragmatic Pacing

The FDA has approved the NeuRx diaphragm pacing system, which uses implanted electrodes to cause the diaphragm to contract and create a breath.

This device is also used for people with spinal cord injuries. If severe respiratory failure has not yet occurred, this device allows people to breathe without a ventilator for up to four hours per day.

Even though the FDA has approved its use, some healthcare providers question its usefulness for ALS,with some specialists even stating it can be harmful.

Percutaneous Endoscopic Gastronomy (PEG)

A feeding tube is placed into the stomach and leads out of the body through the abdominal wall. Although studies have failed to show a consistent impact on survival time, it is considered to be a safe nutritional protocol in patients with a functional gastrointestinal system.

Because a PEG tube bypasses the mouth and throat, the risk of choking and inhaling food and medications into the lungs is minimized. Liquid tube feedings, medications, and water can all be given by PEG tube.

Improving Quality of Life

Physical therapists can help a person with ALS to do physical exercise and stretching that strengthens functioning muscles, decreases spasticity, and doesn't overwork their muscles, with the goal of preserving the strength and flexibility they still have.

Occupational therapists can help with assistive devices that improve functionality and increase independence, such as ramps, braces, walkers, and wheelchairs.

Speech therapists can help teach adaptive strategies to speak more loudly and more clearly. As speech deteriorates, there are adaptive devices like computer-based speech synthesizers using eye tracking technology and even brain-computer interfaces that can control equipment like wheelchairs using only brain activity.

Hopeful Research for ALS

Many researchers and clinical trials are working on trying to find treatments for ALS. Therapies on the horizon involve stem cells that could help to protect remaining motor neurons, plus medications that may treat possible genetic variations that contribute to ALS.

A Word From Verywell

Advances have been made in recent years in the support and treatment for ALS. Researchers have also made advances in understanding the disease process of ALS, which will hopefully lead to new treatments.

Educating yourself on treatment and care options for ALS can help you understand this difficult and complicated diagnosis. A specialized multidisciplinary treatment team for ALS may be most helpful.

Talk to your healthcare provider about what you can do to help the person with ALS live more comfortably, and realize that caregivers will also need a lot of support navigating this difficult illness.

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11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading
  • Pinto S, Carvalho MD. Breathing new life into treatment advances for respiratory failure in amyotrophic lateral sclerosis patients. Neurodegenerative Disease Management. 2014;4(1):83-102. doi:10.2217/nmt.13.74.