Amyotrophic Lateral Sclerosis
Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.
Source: MedlinePlus, National Library of Medicine. Read the original source
MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.
Amyotrophic lateral sclerosis (ALS) is a nervous system disease that attacks nerve cells called neurons in your brain and spinal cord. These neurons transmit messages from your brain and spinal cord to your voluntary muscles - the ones you can control, like in your arms and legs. At first, this causes mild muscle problems. Some people notice:
- Trouble walking or running
- Trouble writing
- Speech problems
Eventually, you lose your strength and cannot move. When muscles in your chest fail, you cannot breathe. A breathing machine can help, but most people with ALS die from respiratory failure.
The disease usually strikes between age 40 and 60. More men than women get it. No one knows what causes ALS. It can run in families, but usually it strikes at random. There is no cure. Medicines can relieve symptoms and, sometimes, prolong survival.
NIH: National Institute of Neurological Disorders and Stroke
Symptoms, tests and care options
Further reading selected by MedlinePlus. Links open the original organizations’ websites.
- ALS Symptoms and Diagnosis · ALS Association
- Diagnosis of ALS · Muscular Dystrophy Association
- Electromyography (EMG) and Nerve Conduction Studies · National Library of Medicine
- Stages of ALS · Muscular Dystrophy Association
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For a life-threatening emergency, call 911 in the U.S. or your local emergency number.
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