Amyotrophic lateral sclerosis (ALS) and multiple sclerosis (MS) both affect your central nervous system. ALS affects motor neurons and has more physical impairments. MS disrupts nerve communication within your brain and spinal cord.

Amyotrophic lateral sclerosis (ALS) and multiple sclerosis (MS) are both neurological disorders affecting the central nervous system (CNS). Each attacks different portions of the body’s nerves and affects muscle movements.

In a few ways, these two diseases are similar. However, their key differences determine a lot about their treatment and outlook:

Amyotrophic lateral sclerosis (ALS)Multiple sclerosis (MS)
affects the motor neurons of the central nervous system (CNS), near the spinal cordaffects the brain and spinal cord
often leaves people paralyzed in its later stagescan affect mobility in its later stages, but rarely leaves people completely debilitated
causes more physical difficultiescauses more cognitive impairment
not proven to be an autoimmune diseasean immune-mediated disease
more common in menmore common in women
most commonly diagnosed between 40 to 70 years oldmost commonly diagnosed between 20 to 50 years old
no known cureno known cure
often debilitating and ultimately fatalrarely debilitating or fatal

Basics about ALS

ALS, also known as Lou Gehrig’s disease, is a chronic, progressive disease. It affects the motor neurons of the nervous system, which are located near the spinal cord.

In a healthy body, motor neurons send signals throughout the body, telling muscles and body systems how to work. ALS rapidly destroys those neurons, preventing them from working correctly.

Eventually, ALS destroys these motor neurons completely. When this happens, the body can’t respond to commands from the brain, and individuals with late-stage ALS become paralyzed.

Basics about MS

MS is a CNS disorder that affects the brain and spinal cord. It destroys the protective coating on the CNS nerves. This interferes with the relay of the instructions from the spinal cord and brain that normally make your body move.

It also prevents sensory signals from reaching the brain, often impairing sensation.

MS is rarely completely debilitating or fatal. Some people with MS will experience mild symptoms for many years of their lives and might not become incapacitated because of it.

However, others may experience a progression of symptoms and become unable to care for themselves.

Both diseases attack certain nerves of the body, affecting muscle and nerve function. For that reason, they share many of the same symptoms, especially in the early stages.

Initial symptoms include:

However, the symptoms then become quite different as the conditions progress.

People with MS often experience cognitive problems, which is rare with ALS. People with ALS typically develop greater physical difficulties.

Symptom of ALS?Symptom of MS?
difficulty walking
involuntary muscle spasms
muscle cramps
muscle weakness
numbness or tingling of the face or body
tripping or falling tendencies
weakness or clumsiness in the hands
difficulty holding your head up or maintaining good posture
dizziness or vertigo
vision problems
slurred speech or difficulty swallowing
sexual dysfunction
bowel problems

ALS commonly starts in the extremities such as the hands, feet, or arms and legs, and affects muscles that a person can control. This includes muscles in the throat.

It can also affect your vocal pitch when speaking. It eventually involves other parts of the body.

People with ALS will eventually develop motor weakness affecting all of their voluntary muscle movements.

ALS has a rapid and consistently worsening onset that’s painless. Progressive muscle weakness is the most common symptom. Issues with thought processes or the five senses aren’t as common in ALS.

However, people in later stages have been known to develop dementia.

People with MS tend to have relapses that usually affect the same few areas or sensation or movement every time, such as the right leg, or the left arm and left leg. And sometimes the effects can become permanent. But people with MS will not develop symptoms affecting all of their muscles.

With MS, symptoms may come and go. MS can affect taste, vision, or bladder control. It can also cause temperature sensitivity as well as weakness to other muscles. Mood shifts are very common with MS too.

For people with ALS, symptoms remain largely physical. In fact, in many people with ALS, mental function remains intact even when most of their physical capabilities have been affected.

However, according to the ALS Foundation, it’s been estimated that up to 50 percent of people with ALS may experience some mild to moderate cognitive or behavioral changes due to the disease.

As it progresses, some people have gone on to develop dementia.

In MS, mental capabilities are usually more affected than in ALS, but MS doesn’t usually cause dementia.

People with MS can experience severe mental changes, including:

Flare-ups and remissions may increase mood shifts and the ability to focus.

MS is an immune-mediated condition. This means that the immune system is involved in the development of the disease.

MS is often considered an autoimmune disease. Autoimmune diseases occur when the immune system mistakenly attacks normal, healthy parts of the body.

ALS isn’t believed to be autoimmune disease. Its cause is largely unknown, but it’s considered a neurodegenerative disorder.

Some possible causes may include:

  • gene mutation
  • chemical toxicity
  • a disorganized immune response

A small number of cases are linked to family history and may be inherited.

MS is far more common than ALS.

MS is estimated to affect over 2.3 million people worldwide, with approximately 1 million of them in the United States.

Around 30,000 people in the United States live with ALS, according to the Hospital for Special Surgery. Over 5,600 people in the country are diagnosed with ALS every year.

There are several risk factors that may affect who develops ALS and MS.


ALS is more common in men than women. The ALS Association estimates that 20 percent more men develop ALS than women.

On the other hand, MS is more commonly seen in women. Women may be three times more likely to develop MS than men, according to the National Multiple Sclerosis Society.

Some researchers suggest that this estimate is actually higher, with women three or four times more likely to develop MS.


ALS is more commonly diagnosed in people between the ages of 40 to 70 years old, although it’s possible to be diagnosed at a younger age. The average age at time of diagnosis is 55 years old.

MS is often diagnosed in people a little younger, with the typical age range for diagnosis being between 20 to 50 years old. As with ALS, it’s possible to be diagnosed with MS at a younger age.

Additional risk factors

Family history increases your risk for both conditions. Both conditions are more prevalent among people of Western European descent and who live in the Northern Hemisphere, although each of the conditions has been diagnosed in every region of the world.

For unknown reasons, U.S. military veterans are up to twice as likely to be diagnosed with ALS or ALS-like conditions as the general public.

Veterans of the Gulf War and members of the Air Force are particularly affected, according to a 2020 study on people who received care from the Veterans Health Administration between 2002 and 2015.

More research is needed to better understand the causes of both conditions.

To make a diagnosis, your doctor will ask for detailed information about your symptoms and your health history. There are also tests they can perform to help make a diagnosis.

If ALS is suspected, your doctor may order electrodiagnostic tests, such as an electromyography or a nerve conduction study.

These tests can measure the activity of the motor neurons, and can show certain patterns that are consistent with a diagnosis of ALS.

A muscle or nerve biopsy may also be recommended for evaluation of ALS.

Your doctor may also order blood and urine samples, or perform a lumbar puncture to examine your spinal fluid.

These tests can show changes that might diagnose or rule out other similar neurological conditions, and a lumbar puncture may show changes consistent with MS.

Doctors can use MRI results to distinguish between MS and other disorders. MS targets and attacks myelin in a process called demyelination.

On the other hand, ALS attacks the motor neurons, and the changes cannot usually be visualized with brain or spine MRIs.

There’s no cure for either condition, but treatments are available.

Treating ALS

ALS treatments are used to help slow symptoms and prevent some complications.

Riluzole (Rilutek) and edaravone (Radicava) are approved by the Food and Drug Administration (FDA) for treatment of ALS. They’re both available as pills.

Tiglutik, which is riluzole in the form of an oral suspension, is also available.

For some people, these medications may slow the disease’s progression. There are other medications that can help you manage symptoms such as constipation, fatigue, and pain.

Occupational, physical, and speech therapy can help manage some effects of ALS. When breathing becomes difficult, you can get devices to assist. Psychological support is also important to help emotionally.

Researchers are looking to find a cure for ALS.

Treating MS

Most medications that are FDA approved for MS are effective for those who have a relapsing form of the disease.

Disease-modifying therapies (DMTs) are approved by the FDA and are available in both injectable and oral forms. These are used on a regular basis to prevent a relapse and can be effective in improving outcomes for relapsing forms of MS.

Recent research efforts have been put into finding more treatments and medications, such as ocrelizumab (Ocrevus), for the progressive forms of the disease. Researchers are also working hard to find a cure.

Treatment plans for MS focus on slowing down the progression of the disease and managing symptoms.

Anti-inflammatory drugs such as cortisone may help block the immune response and are used short term for treatment of MS flare-ups.

Lifestyle remedies and alternative treatments for MS are also important, especially those focusing primarily on stress reduction.

Chronic stress is believed to worsen the neurological symptoms of MS and may even increase the number of brain lesions.

Lifestyle remedies include exercising and relaxation techniques, such as practicing mindfulness. Mindfulness reduces stress and allows for better coping methods in stressful situations.

MS relapses can come without warning and your physical and cognitive abilities can fluctuate in between relapses, so it’s important to be willing to adapt your activities to how you feel on a given day.

However, staying as active as possible and continuing to socialize can help you feel better about your disease and improve your quality of life.

Each condition has a different long-term outlook.

Outlook for ALS

ALS symptoms usually develop very quickly, and it’s considered a terminal condition.

The 5-year survival rate, or the number of people still living 5 years after being diagnosed, is 20 percent, according to the ALS Association. The average survival rate is 3 years after diagnosis.

Around 10 percent of people with ALS survive more than 10 years.

According to the National Institute of Neurological Disorders and Stroke, all people with ALS will eventually become unable to walk, stand, or move about without help.

They are also likely to develop great difficulty swallowing and chewing.

Outlook for MS

MS symptoms usually develop slowly, and MS affects quality of life, but it isn’t fatal.

Symptoms of MS may come and go, depending on the type of MS.

You may experience a flare-up, and then symptoms almost completely resolve for days, weeks, or even years.

Usually, there are some residual symptoms in between flare-ups, and often there’s an overall permanent decline in cognitive or physical function after each flare-up.

The progression of MS differs from person to person. Most people with MS fall into one of these four categories of the disease:

  • Clinically isolated syndrome (CIS): CIS is a single episode of neurological symptoms. It’s caused by inflammation and damage to the myelin covering on nerves in the brain or spinal cord. CIS can, but doesn’t always, evolve into MS.
  • Relapsing-remitting MS (RRMS): RRMS is the most common form of MS. Relapses are followed by almost full recovery. There’s little progression of the disease after flare-ups.
  • Secondary progressive MS (SPMS): Sometimes RRMS can become SPMS when the disease significantly progresses after flare-ups or relapses.
  • Primary progressive MS (PPMS): Neurologic function begins to worsen from the very beginning of PPMS. Disease progression varies and levels off from time to time, but there are no remissions.

Though both diseases appear to have a few features in common during the earliest stages, the progression, treatments, and outlook for ALS and MS are very different.

However, in both cases, treatment paves the path toward a healthier, more fulfilling life for as long as possible.

People with either condition should talk with their doctor about developing a treatment plan. Your doctor can also prescribe medications that can help you manage your symptoms.