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Amyotrophic Lateral Sclerosis (ALS)

Stages of ALS

ALS is a relentlessly progressive disorder. The rate of progression between individuals is variable and the history generally reflects gradual and progressive worsening over time until death occurs.

Early stages


  • Muscles may be weak and soft, or they may be stiff, tight, and spastic. Muscle cramping and twitching (fasciculation) occurs, as does loss of muscle bulk (atrophy).
  • Symptoms may be limited to a single body region or mild symptoms may affect more than one region.

Physical effects

  • The person may experience fatigue, poor balance, slurred words, a weak grip, tripping when walking, or other minor symptoms.
  • Sometimes this stage occurs before a diagnosis is made.

Middle stages


  • Symptoms become more widespread.
  • Some muscles are paralyzed, while others are weakened or unaffected. Fasciculations may continue.

Physical effects

  • Unused muscles may cause contractures, in which the joints become rigid, painful, and sometimes deformed.
  • If a fall occurs, the person may not be able to stand back up alone.
  • Driving is relinquished.
  • Weakness in swallowing muscles may cause choking and greater difficulty eating and managing saliva.
  • Weakness in breathing muscles can cause respiratory insufficiency, especially when lying down.
  • Some people experience bouts of uncontrolled and inappropriate laughing or crying (pseudobulbar affect). Despite how it seems, the person usually doesn’t feel particularly sad or happy.

Late stages


  • Most voluntary muscles are paralyzed.
  • The muscles that help move air in and out of the lungs are severely compromised.

Physical effects

  • Mobility is extremely limited, and help is needed in caring for most personal needs.
  • Poor respiration may cause fatigue, fuzzy thinking, headaches, and susceptibility to pneumonia. (Respiratory insufficiency is a leading cause of death in ALS.)
  • Speech, or eating and drinking by mouth, may not be possible.

End stage

  • The vast majority of deaths in ALS are the result of respiratory failure, a process that progresses slowly over months. Medications can relieve discomfort, anxiety, and fear caused by respiratory insufficiency.
  • Far less-common causes of death in ALS include malnutrition as a result of swallowing problems, pulmonary embolism (a blockage in one of the arteries of the lungs), abnormalities in the heart’s electrical pacing system called cardiac arrhythmias, and pneumonia as the result of aspiration (when food or fluid gets into the lungs).
  • Hospice care (in a facility or in the home) focuses on providing comfort and maintaining quality of life by supporting the physical, emotional, and spiritual needs of the individual with ALS and their family members. Families should contact hospice early on to see what in-home services are available even before the most advanced stage.
  • At MDA clinics, physicians work closely with palliative care teams to coordinate treatment with in-home hospice care providers, assisted living facilities, or inpatient hospice settings. Such cooperation helps ensure the person with ALS has the most peaceful and painless experience possible.

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