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ALS Overview
Amyotrophic lateral sclerosis (ALS), also known as Motor Neuron Disease (MND), Lou Gehrig's Disease, and Charcot's disease, is a progressive neurodegenerative disease that attacks motor neurons in the brain and spinal cord. This results in the wasting away of muscle, loss of movement and eventual paralysis. There are an estimated 30,000 people living with ALS in the United States at any given time. Every 90 minutes, someone is diagnosed with ALS. About 90% of all ALS cases are sporadic with no known history of the disease in a family. The remaining 10% of cases are known as familial ALS.
Video: What is ALS?
ALS can affect anyone of any age, gender or race. However, for the most part, ALS affects people between the ages of 40 and 70.
Some early signs and symptoms of ALS include:
  • muscle cramps and muscle twitching
  • weakness in hands, legs, feet or ankles
  • difficulty speaking or swallowing
The senses, including hearing, sight, smell, taste, and touch, are not affected by ALS. In most cases of ALS, cognitive function is not affected.
ALS is not experienced in the same way among all those diagnosed, and the manner and speed at which the disease moves throughout a person's body can vary greatly. Most people live about 3-5 years after they experience their first signs of disease, with one in ten people surviving at least 10 years. The variable rate of disease progression makes prognosis difficult to predict and therapies challenging to develop.

Is there a cure for ALS?

Currently, there are no effective cures or treatments to stop disease progression of ALS. ALS is a complex disease which varies from person to person. Far more research is necessary to discover effective treatments for each person living with ALS. That's why researchers at the ALS Therapy Development Institute (ALS TDI) are working hard each day to find ALS treatments. We aim to do this by identifying, testing, and developing promising new treatments and learning more about ALS through our Precision Medicine Program (PMP).
ALS Causes

What causes ALS?

Amyotrophic lateral sclerosis, ALS, is caused by progressive deterioration and death of motor neurons, leading to muscle weakness and paralysis.
Ten percent of cases are known as familial ALS,in which a specific genetic mutation is inherited and passed down from generation to generation. Over 29 ALS-specific genetic mutations have been identified to date [1]. The most common known genetic mutation in ALS is the C9orf72 gene, which accounts for approximately 30 to 40 percent of all familial ALS cases [1]. Mutations in the SOD1 gene make up around 20 percent of familial ALS, and TARDBP and FUS gene mutations each account for about 5 percent of familial cases.
The remaining 90 percent of cases are known as sporadic ALS, meaning there is no known history of the disease in a family. There are many theories outlining potential causes of ALS including oxidative stress, mitochondrial dysfunction, immune system over activity, glutamate toxicity and toxic exposures. Studies have shown that those who have served in the military are more likely to develop ALS than the general population [2], [3]. It is important to note that clinically, familial ALS and sporadic ALS appear to be indistinguishable from one another.

Who gets ALS?

ALS can affect anyone of any age, gender or race.
However, for the most part, ALS affects people between the ages of 40 and 70. ALS appears to affect men at a higher rate than women below the ages of 65. Over the age of 70, incidence appears to be the same. According to recent research, incidence of ALS appears to be greater in white populations than in African American, Asian or Hispanic populations [4] [5].

How is ALS Diagnosed?

There is no single diagnostic tool for ALS. The El Escorial criteria is commonly used to aid diagnosis, which requires the following:
  1. Evidence of lower motor neuron (LMN) degeneration by clinical, electrophysiological or neuropathologic examination.
  2. Evidence of upper motor neuron (UMN) degeneration by clinical examination.
  3. Progressive spread of symptoms or signs within a region or to other regions, as determined by history or examination.
However, these criteria are limited. A series of clinical procedures may also be conducted to rule out neurological conditions whose symptoms closely resemble ALS. This means the ALS diagnostic process includes eliminating the possibility of many other diseases along the way, including infections like Lyme disease and other neurological disorders such as multifocal motor neuropathy, before making a final diagnosis. For this reason, diagnosis can take as long as 12 to 14 months in some cases.
Throughout the diagnostic process, people might receive a diagnosis of suspected, possible, probable or definite ALS. These designations depend on which parts of the body are affected by the disease. Without a definite diagnosis, people with possible or probable ALS nevertheless remain eligible to participate in a growing number of clinical trials evaluating emerging treatments for the disease. For a full list of ALS studies, visit our clinical trials page.
Some of the procedures a person may undergo on their way to an ALS diagnosis may include:
Genetic testing
When a familial case of ALS (fALS) is suspected, genetic testing might also be recommended. Commercially available tests can identify dozens of ALS-linked genes. Those that undergo genetic testing are typically provided genetic counseling, during which they learn how to interpret results.
Electromyography and nerve conduction studies
These tests enable clinicians to check whether motor nerves are plugged into the muscles and are working properly. Nerve conduction studies (NCS) test whether the motor nerves can send signals of sufficient strength to enable movement of the muscles. Electromyography (EMG) tests measure the ability of these muscles in response to these signals to trigger contraction. These tests help rule out certain disorders including those of the peripheral nerves.
Muscle Biopsy
Clinicians may also recommend a biopsy to further investigate affected muscles. Examination of muscle tissue under the microscope can help rule out certain muscle diseases.
Magnetic Resonance Imaging (MRI)
MRI enables clinicians to examine organs and tissues including the brain and spinal cord. An MRI can help rule out a number of conditions including brain tumors, multiple sclerosis and certain disorders of the spinal cord.
Other tests
These include blood and urine tests and spinal tap. However, researchers hope to expedite the diagnostic process by developing tools that directly indicate whether a person has the disease.
Emerging tools
A growing number of researchers suspect that MRI could indicate whether a person has ALS rather than just eliminate other diseases. Researchers hope certain biomarkers can be used to identify people who are at high risk of developing ALS before they show symptoms.
Meanwhile, other scientists are developing a new method called electrical impedance myography (EIM) to diagnose ALS. This test helps identify changes in affected muscles including atrophy. Scientists hope that this tool might also predict the spread of ALS and aid in the development of treatments for the disease.

What is the Prognosis of ALS?

Most people with ALS live about 3-5 years after experiencing their first signs of the disease. At least one in ten people live more than 10 years following their diagnosis. This variable rate of progression makes predicting prognosis difficult. Clinicians instead rely on regular follow-up visits to monitor people with ALS to manage their disease.

Early Signs of ALS

Most people with ALS first feel muscle cramps, spasms or twitching (fasciculations) in one of their arms or legs. Other signs include weakness in the hands and feet or loss of balance. This form of the disease is called limb-onset ALS.
About 25 percent of people with ALS first have trouble talking clearly and begin to slur their words. This form of the disease is called bulbar-onset ALS.

Monitoring ALS

After receiving a diagnosis, people with ALS often schedule regular clinic visits every 3-4 months. During these visits, patients are monitored for changes in their functional abilities. Commonly used tests for monitoring ALS include:
This is a test that measures lung function. Breathing abilities are typically estimated based on the maximum amount of air that can be blown out either slowly (slow vital capacity - SVC) or quickly (forced vital capacity - FVC).
ALS Functional Rating Scale-Revised (ALSFRS-R)
The ALSFRS-R is a rating scale that measures changes in a person's abilities, including breathing, speaking, sleeping, swallowing, and walking. The score is based on answers to 12 questions using a 48-point scale. Individuals with ALS can track their disease at home using the ALSFRS-R scale, there are several websites that offer that service free of charge, such as PatientsLikeMe.
ALS Research Collaborative (ARC)
Through the ALS Research Collaborative (ARC), researchers at ALS TDI partner with people with ALS around the world to share and gather data on medical histories, family histories, genetics, biomarkers, and patient cell biology to better understand the disease. Participants are provided with a secure online portal where their data is located and easily accessible. They are able to track their own disease progression and follow how various interventions impact their symptoms and progression.
Clinic Visits
Following clinic visits, individuals with ALS should consider asking for access to the “data” obtained during the visit, such as the doctor's recorded ALSFRS-R and SVC or FVC scores. This information is used as enrollment criteria for most clinical trials, and having it at hand can allow people to quickly determine if they qualify for participation in a trial.

Middle Stages of ALS

As the disease spreads, many muscles weaken and start to stiffen. Range of motion exercises will likely be recommended by physical therapists to help keep muscles loose and prevent the formation of contractures and muscle pain.
A person with ALS's breathing may become affected. A BiPAP machine or a phrenic pacer might be suggested, particularly to help improve sleeping. A feeding tube might be recommended to help meet nutritional needs. Medications might be also recommended to help control pseudobulbar affect (uncontrolled laughing or crying) or to help reduce muscle spasms.
People with bulbar-onset often work with a speech therapist to keep their ability to speak for longer. Those with limb-onset ALS may rely on a cane, walker, or wheelchair due to difficulties walking and maintaining balance.
In most cases of ALS, cognitive function is not affected. However, over the past 10 years there has been an increasing interest in investigating the overlap of ALS with Frontotemporal Dementia (FTD), another neurological disease characterized by a decline in cognitive function. It is believed that up to a third of those diagnosed with ALS may be affected by cognitive issues.

Late Stages of ALS

As ALS progresses and a person's muscles become paralyzed, they may lose the ability to move and speak. Many people with ALS may require a wheelchair to get around. Some may communicate through assistive devices like an eye-tracking device or a letter board. Some people with ALS choose invasive ventilation by having a tracheostomy tube to help keep them breathing. People with late-stage ALS are often cared for at home or in hospice.
Treatments for ALS
There are currently no effective cures for ALS or treatments to stop disease progression, but scientists are working hard to develop therapies for this disease. There are currently only two treatments approved by the FDA in the United States. They are riluzole (marketed as Rilutek or Tiglutik) and edaravone (marketed as Radicava).
Much more is known about the use of riluzole in ALS as it was approved in the 1990s. Its effects are modest, extending life by about two to three months. In May 2017, edaravone was approved by the FDA. Clinical trials of edaravone showed that those who began getting infusions of the medication early on in their disease had the greatest potential to maintain muscle function. While neither of these treatments have been shown to halt the progression of ALS, some people who take either or both of them may experience a positive impact on their progression. Both riluzole and edaravone are available today. People with ALS are encouraged to speak with their doctor to determine if these treatments are right for them.
ALS is a complex, multi-system disease. A growing number of ALS clinics are deploying multidisciplinary teams to care for and meet the physical, emotional, and nutritional needs of people with ALS. These palliative care teams include physical, respiratory, speech, and occupational therapists to help people with ALS breathe easier, keep moving, and stay connected.
Today, there are dozens of potential treatments in clinical trial that are enrolling people with ALS and their families. You can visit our ALS Treatments and Drugs page to read more about potential therapies for ALS. For more information on enrollment our page to read more about potential therapies for ALS. For more information on enrollment and inclusion criteria for clinical trials, visit our clinical trials page.