What is ALS?
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Amyotrophic lateral sclerosis (ALS) commonly known as Lou Gehrig's disease is a progressive neuromuscular illness. In ALS, there’s a gradual, continuing degeneration of motor nerve cells in the brain (upper motor neurons) and spinal cord (lower motor neuron).

When motor neurons can no longer send impulses to muscles, they begin to waste away (atrophy), causing increased muscle weakness and paralysis.

Amyotrophic lateral sclerosis does not impair a person's intellectual reasoning; vision; hearing; or sense of taste, smell and touch. In most cases, ALS does not affect a person's sexual, bowel or bladder abilities. ALS is often referred to as a syndrome because the disease can assume different patterns of onset and intensity. Loss of muscle function, however, characterizes all cases.

ALS occurs rarely and spontaneously. To date, except in strongly genetic forms of the disease, the cause of amyotrophic lateral sclerosis remains a mystery. And though a great deal is known about ALS biology, how it starts in the body also isn’t clear.

Here are some quick reference facts about ALS:

  • Most people who develop ALS are between the ages of 40 and 75, with the majority after age 60, although it can occur at a younger age.
  • The disease is relatively rare; the incidence is roughly 2 people per 100,000 per year.
  • Most surveys hold that ALS is more common in men than women, though that gap may be closing.
  • The incidence of ALS is five times higher than Huntington’s disease and about half that of multiple sclerosis.
  • While there’s no cure, riluzole therapy improves ALS survival for typical patients by a short period of time, around four to six months.
  • ALS occurs throughout the world with no obvious racial, ethnic or socioeconomic boundaries.