Amyotrophic lateral sclerosis (ALS)

Amyotrophic lateral sclerosis, or ALS, is a progressive disease that causes loss of muscle control due to deteriorating nerve cells in the brain and spinal cord. ALS is also known as Lou Gehrig’s disease, named after the famous Yankees baseball player who was diagnosed with it.

According to the ALS Association, around 6,400 people in the United States are diagnosed with ALS every year and around 20,000 Americans are currently living with the disorder.

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Symptoms of ALS

Symptoms of ALS vary greatly from person to person, depending on which neurons are affected. Signs and symptoms might include:

  • Cognitive and behavioral changes.
  • Difficulty walking or doing normal daily activities.
  • Hand weakness or clumsiness.
  • Inappropriate crying, laughing or yawning.
  • Muscle cramps and twitching in your arms, shoulders and tongue.
  • Slurred speech or trouble swallowing.
  • Tripping and falling.
  • Weakness in your legs, feet or ankles.

Diagnosing ALS

The symptoms of ALS mimic other neurological diseases, making early diagnosis difficult. Because of this, doctors will perform several different tests to help rule out similar conditions. Some of these tests include:

Electromyogram (EMG). This test evaluates the electrical activity of various muscles while contracting and when at rest. Abnormalities doctors see in muscles can help them confirm, or rule out, ALS.

Nerve conduction study. By seeing how well your nerves can send impulses to muscles in different areas of your body, this test helps doctors decide if there’s nerve damage anywhere and if certain muscle or nerve diseases are present.

MRI. Magnetic Resonance Imaging (MRI) produces detailed images of your brain and spinal cord that can show doctors tumors on the spinal cord, herniated discs in your neck or other conditions that might be causing your symptoms.

Blood and urine tests. Doctors can analyze samples of your blood and urine to help eliminate other possible causes of your signs and symptoms.

Spinal tap. This procedure, also called a lumbar puncture, checks for abnormalities in antibodies by removing a small sample of cerebrospinal fluid from your spinal canal.

Muscle biopsy. This procedure can help your doctor determine if you have a muscle disease or condition rather than ALS.

Under local anesthesia, a small portion of your muscle is removed and sent to a lab for analysis.

The main types of ALS

Sporadic ALS

Around 95% of ALS diagnoses are considered sporadic, meaning the disease occurs randomly. Although sporadic ALS means no risk factors and no family history of the disease is present, family members are at an increased risk for the disease. However, the overall chance of developing ALS remains very low.

Familial (Genetic) ALS

As the name suggest, familial ALS means the disease was inherited from a parent. About 5% to 10% of all ALS cases are familial, and usually only requires one parent to carry the disease-causing gene.

More than a dozen gene mutations have been found to cause familial ALS.

Treatments for ALS

Since there is currently no cure for ALS, treatments focus on slowing the progression of the disease, preventing complications and making day-to-day life as comfortable as possible.

Your team of healthcare providers will help you select the right treatments for you. As always, you can accept or refuse any of the treatments suggested.

Frequently asked questions (FAQs) about ALS

What is usually the first sign of ALS?

ALS usually first appears in one of the extremities, like an arm or a leg, or in a person’s speech. When symptoms start in the arms or legs, it’s called “limb onset” ALS, and when symptoms appear in speech, it’s called “bulbar onset” ALS.

Other early symptoms include:

  • Difficulty chewing or swallowing.
  • Muscle cramps.
  • Muscle twitches in the arm, leg, shoulder or tongue.
  • Muscle weakness affecting an arm, a leg, the neck or diaphragm.
  • Slurred and nasal speech.
  • Tight and stiff muscles (spasticity).
What happens when you have ALS?

ALS gradually destroys the nerve cells (motor neurons) that control voluntary muscle movements such as walking and talking, causing them to eventually die. When this happens, the motor neurons are no longer capable of sending messages to the muscles in the body, so the muscles stop working.

What are the complications of ALS?

As the disease progresses, ALS causes problems breathing, speaking and eating.

Breathing problems. As it progresses, ALS slowly paralyzes the muscles used to breathe. Over time, that paralysis makes breathing on your own impossible, and eventually causes death.

Respiratory failure is the most common cause of death for people with ALS, occuring, on average, within three to five years after symptoms begin. However, some people with ALS live 10 or more years after diagnosis.

To assist with breathing at night, you might need a device like a continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP). These are the same types of machines people with sleep apnea use to help them breathe while sleeping.

Speaking problems. Most people with ALS eventually have problems speaking. Typically beginning with a mild slurring of words, it soon progresses to become more noticeable and more serious. As it becomes more difficult to be understood, people with ALS often seek out alternate communication technologies in order to help them communicate effectively.

Eating problems. Because the muscles that control swallowing slowly become damaged over time, people with ALS can develop dehydration and malnutrition. This also increases their risk of food, liquids or saliva entering their lungs. If this happens, it can cause pneumonia. To avoid these problems, a feeding tube may be used.

Does ALS affect thinking?

Although ALS primarily affects muscles in the body, changes in cognitive ability are also fairly common, occurring in around 50% of people with ALS. The changes in cognitive ability range from minor symptoms to full-blown dementia.

Is it true that military veterans get ALS more often?

Some studies suggest that military veterans are about 1.5 to 2 times more likely to develop ALS. The cause is unknown, but suggested reasons include exposure to lead, pesticides and other environmental toxins.

ALS is recognized as a service-connected disease by the U.S. Department of Veterans Affairs.

What is the long-term outlook for people with ALS?

After being diagnosed, the typical life expectancy for a person with ALS is two to five years. Approximately 20 percent of patients live with ALS for more than five years, and 10 percent of patients live with the disease for more than 10 years.

Notably, certain ALS patients live considerably longer. Stephen Hawking, the renowned English astrophysicist, lived over 50 years after he was diagnosed with the disease.

What kind of research is being done about ALS?

Many neurological disorders do not have effective treatment options. Clinical trials (also called research trials) offer hope for many people and an opportunity to help researchers find better ways to safely detect, treat or prevent disease.

Finding clinical trials

For more information about finding clinical trials on ALS, visit  Use the search terms “amyotrophic lateral sclerosis” or “ALS AND (your state)” to locate trials in your area.

National ALS Registry

The National ALS Registry is a program to collect, manage and analyze data about people with ALS in the United States. Developed by the Center for Disease Control and Prevention’s Agency for Toxic Substances and Disease Registry (ATSDR), this registry establishes information about the number of ALS cases, collects demographic, occupational and environmental exposure data from people with ALS to learn about potential risk factors for the disease, and notifies participants about research opportunities. The Registry includes data from national databases as well as de-identified information provided by individuals with ALS. All information is kept confidential.

People with ALS can add their information to the Registry by visiting


The ALS Association. What is ALS? – Amyotrophic Lateral Sclerosis (

National Institute of Neurological Disorders and Stroke (NINDS). Amyotrophic Lateral Sclerosis (ALS) Fact Sheet (

Center for Disease Control and Prevention (CDC). Amyotrophic Lateral Sclerosis (ALS) (