What is als

Last updated: April 1, 2026

Quick Answer: ALS, or Amyotrophic Lateral Sclerosis, is a progressive neurodegenerative disease that affects nerve cells in the brain and spinal cord, causing loss of muscle control and eventual paralysis.

Key Facts

Understanding ALS

Amyotrophic Lateral Sclerosis (ALS) is a serious neurodegenerative disease that progressively destroys motor neurons—the nerve cells that control voluntary muscle movements. The name itself describes the disease: amyotrophic refers to muscle wasting, lateralsclerosis means scarring or hardening. As these neurons degenerate, muscles gradually weaken and patients lose the ability to move, speak, eat, and eventually breathe.

Symptoms and Progression

ALS typically begins with subtle symptoms that may include muscle weakness in the arms or legs, slurred speech, or difficulty swallowing. As the disease progresses, paralysis spreads throughout the body. Most people maintain their cognitive abilities throughout the disease, though some experience changes in behavior or reasoning in the later stages. The progression varies widely—some people experience rapid decline over months, while others progress more slowly over years. Early detection and intervention can help manage symptoms and extend survival time.

Types of ALS

There are several recognized forms of ALS. Sporadic ALS is the most common form, accounting for about 90% of cases, with no clear genetic cause. Familial ALS (FALS) runs in families and accounts for about 10% of cases. Additionally, Primary Lateral Sclerosis and Progressive Muscular Atrophy are rarer variants that share similarities with classic ALS but progress differently or affect different neuron populations.

Diagnosis and Testing

Diagnosing ALS typically involves a combination of clinical examination, electromyography (EMG) tests to measure muscle electrical activity, nerve conduction studies, and sometimes MRI scans to rule out other conditions. Blood tests may be used to exclude other diseases. There is no single definitive test for ALS, so diagnosis often requires eliminating other possible conditions first. Early accurate diagnosis is important for beginning treatment that may slow progression.

Treatment and Management

While ALS cannot currently be cured, several treatments can help manage symptoms and extend survival. Riluzole and edaravone are FDA-approved medications that may slow disease progression. Physical therapy, occupational therapy, speech therapy, and nutritional support help maintain quality of life and independence. Many patients eventually require mechanical ventilation to assist with breathing, and palliative care becomes increasingly important as the disease advances.

Related Questions

What is the average life expectancy after ALS diagnosis?

Average life expectancy is 2-5 years from diagnosis, though some people live 10 or more years. Factors affecting survival include age at onset, disease progression rate, and respiratory muscle involvement.

Can ALS be prevented or inherited?

Sporadic ALS cannot be prevented, with no known cause. Familial ALS runs in families with identified genetic mutations. Genetic counseling helps families understand inheritance patterns and risks.

What resources are available for ALS patients and families?

The ALS Association and Muscular Dystrophy Association provide support groups, equipment assistance, research funding, and patient services. Local chapters offer community resources and financial aid for care.

Sources

  1. Wikipedia - Amyotrophic Lateral Sclerosis CC-BY-SA-4.0
  2. The ALS Association