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Amyotrophic Lateral Sclerosis (ALS)

(Lou Gehrig Disease; Lou Gehrig's Disease)


The Manual's Editorial Staff

Reviewed/Revised Jul 2022 | Modified Sep 2022
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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.

Amyotrophic Lateral Sclerosis (ALS)

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.

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:

How do doctors treat ALS?

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

Doctors treat your symptoms with:

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 Advance Directives Health care advance directives are legal documents that communicate a person’s wishes about health care decisions in the event the person becomes incapable of making health care decisions. There... read more . 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.

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