9 Early Signs of ALS

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Amyotrophic lateral sclerosis (ALS) affects the motor neurons (nerve cells) that control voluntary movement. The early symptoms of ALS tend to affect your extremities or sometimes your breathing and eating. Over time, movement, speech, chewing and swallowing, and breathing are affected.

This article discusses nine early signs of ALS and what happens after a person is diagnosed with the condition.

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First Signs of ALS

The early signs of ALS appear when muscles start to weaken, and they can vary from person to person. Initially, the signs can be so slight they are not noticeable. They may affect one or several parts of the body.

In many people, the first signs appear in the arms and legs, which is called limb onset. In about one-third of people with ALS, symptoms begin with speech or swallowing difficulties, called bulbar onset.

Early signs typically include:

  • Changes in motor control of arms and hands: One hand or arm becomes weak, followed by the other a few weeks or months later. It may become more difficult to button a shirt or unlock a door. People may begin to drop things more often.
  • Leg weakness: ALS usually affects one leg first, which can lead to trips, stumbles, and falls. The other leg becomes weak over time, making walking difficult.
  • Muscle stiffness (spasticity): Muscle tone increases until the muscles become so tight it interferes with normal movement.
  • Muscle twitches and cramps (fasciculation): Muscle twitches often occur during sleep. They tend to affect the hands and feet but may also affect the tongue.
  • Slurred speech (dysarthria): This is often described as "thick" speech. Weakening facial muscles and loss of sensation can make speech sound nasal, and it may be difficult to project the voice.
  • Difficulty swallowing (dysphagia): This is due to weakened facial and tongue muscles.
  • Breathing difficulties (dyspnea): Shortness of breath is less common as an early sign.
  • Fatigue: General tiredness and fatigued extremities may be experienced.
  • Uncontrolled laughing or crying (pseudobulbar affect): This is possibly due to disruption in the brain's neural circuits. It is not tied to emotions. Crying is more common than laughing.

How to Confirm Suspected ALS

ALS is a difficult disease to diagnose. There is no specific test to confirm it. Healthcare providers reach a diagnosis through a series of tests and examinations, including:

  • Neurological examination: This exam tests muscle strength, dexterity, reflexes, and coordination.
  • Electromyography (EMG): This test measures electrical activity in muscles.
  • Nerve conduction velocity test (NCV): This test measures how fast an electrical impulse travels through a nerve.
  • Blood tests: These are done to rule out conditions that may have symptoms similar to ALS.
  • Urine tests: Tests for heavy metals may be done on people who may have been exposed to them. These may be toxic to the nerves and may be connected to ALS, though it has not been confirmed.
  • Imaging studies: These include X-rays and magnetic resonance imaging (MRI). These tests can also rule out ALS and help find other causes for symptoms.
  • Muscle biopsy: Rarely, small pieces of tissue are collected and examined to look for evidence of muscle diseases that may have some symptoms similar to ALS.

Since ALS is a progressive disease, healthcare providers can compare muscle strength and motor ability over time, which can also help lead to a diagnosis.

Should I Get Genetic Testing for ALS?

Only about 10% of ALS cases are hereditary. If you have ALS, you can get a genetic test to determine if you have a hereditary form, which may tell you something about how it may progress and how likely it is that your children may get it.

If you have a family member with ALS, the choice to be tested is personal—it's up to you. Often, people who pursue a genetic test will be required to have a neurological exam, a psychological assessment, and genetic counseling beforehand.

What Happens After Diagnosis

The path of ALS varies from person to person, though it is a progressive disease that eventually affects life-sustaining abilities. ALS is a terminal diagnosis (cannot be cured and will lead to death), but up to 10% of people stabilize after a while, and their symptoms don't worsen for as long as 10 or 20 years.

Take the time to learn about ALS, understand what kinds of decisions you need to make for yourself and your family, and consider looking for a support group.

If you want a second opinion, look for a clinic or center that specializes in ALS. Stay abreast of research and clinical trials that are actively looking for effective treatments. Though there is no cure at this time, there are new medications available that may slow the progression of ALS to a limited degree.

Specialists can suggest exercise regimens, assistive and communication devices when needed, do home assessments to facilitate daily activities, and help with eating and breathing support when necessary.


ALS is a disease that makes your muscles weaken over time, including your arms and legs and the muscles you use to eat and breathe. Early signs include clumsiness, dropping things, and tripping or stumbling due to weakness in the arms and legs. Fewer people have difficulty with speech or breathing as early signs of ALS.

ALS is not easy to diagnose, but healthcare providers can perform a series of exams and tests to reach a diagnosis, in part by ruling out other diseases that may look similar.

Most cases of ALS are not hereditary, but there are genetic tests available for people who choose to have them if ALS runs in their family or they have the condition and want to know which form they have.

A Word From Verywell

ALS is a devastating diagnosis, but there are real signs of hope coming from research into new treatments. Recently, new medications have been approved that can have some effect in slowing disease progression. There are other potential treatments on the horizon, including stem cell therapies.

Frequently Asked Questions

  • What is the average age of onset for ALS?

    ALS almost always occurs in adults. Symptoms tend to begin in people between 55 and 75 years old.

  • Are the early signs of ALS constant?

    Early signs and symptoms of ALS may be difficult to detect, but they progress rather than come and go. In the initial stages, they often affect one arm or leg first, followed by the other limb in a few weeks or months.

  • How long does it take to get diagnosed with ALS?

    ALS is not easy to diagnose, and it can take up to a year to confirm it. Sometimes, healthcare providers have to follow up with the person to see if their symptoms worsen, which can help confirm the diagnosis. There are also tests and imaging studies that can help rule ALS out or in.

10 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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  2. National Institute of Neurological Disorders and Stroke. ALS fact sheet.

  3. Massachusetts General Hospital. Diagnosing ALS.

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  5. MedlinePlus. Amyotrophic lateral sclerosis.

  6. ALS Association. FYI: reasons for living with ALS.

  7. Yale Medicine. New ALS drug: what you need to know.

  8. Lin TJ, Cheng GC, Wu LY, et al. Potential of cellular therapy for ALS: current strategies and future prospects. Front Cell Dev Biol. 2022;10:851613. doi:10.3389/fcell.2022.851613

  9. ALS Curtis Vance Foundation. Do ALS symptoms come and go?

  10. ALS Foundation. Obtaining an ALS diagnosis.

By Nancy LeBrun
In addition to her extensive health and wellness writing, Nancy has written about many general interest topics for publications as diverse as Newsweek, Teen Vogue, abcnews.com, and Craftsmanship Quarterly. She has authored a book about documentary filmmaking, a screenplay about a lost civil rights hero, and ghostwritten several memoirs.