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Quick Facts

Amyotrophic Lateral Sclerosis (ALS)

(Lou Gehrig Disease; Lou Gehrig's Disease)


The Manual's Editorial Staff

Last full review/revision Jul 2020| Content last modified Jul 2020
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Your muscles move when your brain sends a signal to them through your nerves.

Motor neurons are the nerves that send your muscles the signals to move. Signals travel from the brain through your spinal cord and nerves to your muscles.

Motor neuron diseases are diseases that slowly destroy your motor neurons. When motor neurons stop working, your muscles don’t get the signal to move.

What is ALS?

Amyotrophic lateral sclerosis (ALS) is the most common type of motor neuron disease. It’s often called Lou Gehrig disease. Lou Gehrig was a famous baseball player in the 1930s who had ALS.

  • ALS comes on very slowly

  • Your muscles gradually become weak and stiff

  • Eventually you won't be able to walk, talk, or swallow

  • If you can't swallow, you'll need a feeding tube

  • If your breathing muscles are affected, you'll need to go on a ventilator (machine to help you breathe)

  • There isn’t a cure, but medicines can help with symptoms

  • About half of people with ALS die within 3 years, but some live more than 10 years

There are several other types of motor neuron diseases, including primary lateral sclerosis, progressive bulbar palsy, and progressive muscular atrophy. These all cause weakness and severe disability.

What are the symptoms of ALS?

Early symptoms of ALS include:

  • Clumsiness and weakness in your hands

  • Sometimes, weakness in your feet, mouth, or throat

  • Muscle cramps

  • Weight loss

  • Feeling very tired

Muscle weakness makes it hard to control the expression on your face. You'll start to have trouble swallowing and may choke on liquids or drool. Your voice may not sound right.

Muscles that aren't used start to shrink and tighten up. You may first notice shrinking in the muscles of your hands.

The weakness slowly gets worse and starts to affect other muscles. Eventually, muscles all over your body are affected, except the muscles that move your eyes.

Later on as your weakness gets worse you may:

  • Need help eating and getting dressed

  • Have twitching muscles

  • Need help walking and eventually need to be in a wheelchair

  • Be unable to swallow without choking and need a feeding tube

  • Have trouble breathing

Eventually your breathing trouble will get so bad that you'll need to be put on a ventilator (breathing machine).

ALS doesn't affect your mind, so you can still think clearly even when the weakness has gotten bad. However, ALS may affect your emotions so you laugh or cry without reason. Also, it's common to be depressed because of how serious the illness is.

How can doctors tell if I have ALS?

Doctors do tests to diagnose your ALS, such as:

  • MRI (an imaging test that uses a strong magnetic field to create a detailed picture of the inside of your body)

  • Electromyography (a muscle test that uses small needles to record the electrical activity of your muscle)

  • Nerve conduction studies (a nerve test that uses small electric shocks to tell how well a nerve conducts signals)

  • Blood tests

  • Urine tests

  • Spinal tap (a test that uses a sample of fluid taken from your spinal canal)

  • Genetic tests (a test that uses a small sample of your blood, skin, or other tissue to look for problems that run in families)

How do doctors treat ALS?

There's no cure for ALS or other motor neuron diseases.

Doctors treat your symptoms with:

  • Physical therapy to keep your joints flexible and slow muscle wasting

  • Occupational therapy to prevent choking while eating, or a feeding tube into your stomach if you can no longer swallow

  • Medicines to help with muscle twitches or cramps

  • Medicine to help with emotional outbursts or depression

  • Medicine to help with drooling

  • Medicine for pain

  • A ventilator (breathing machine) if you're too weak to breathe on your own

Even with feeding tubes and ventilators, about half of people with ALS die within about 3 years. However, some people live over 10 years and very rarely 30 or more.

If you have ALS or one of the other dangerous motor neuron diseases, you may want to make an advance directive. An advance directive is a plan to let your loved ones and doctors know what kinds of medical care you want at the end of your life.

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
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