Signs and Symptoms

At first, symptoms of ALS may be barely noticed. But over time, the disease worsens. As nerve cells die, the muscles they control stop acting and reacting correctly.

  • Arms and legs may lose strength and coordination.
  • Feet and ankles may become weak.
  • General fatigue may develop
  • Muscles in the arms, shoulders and tongue may cramp or twitch.
  • Swallowing, speaking and breathing may become difficult.

Eventually, ALS weakens muscles, including muscles used for breathing, until they become paralyzed. Unable to swallow, patients with ALS may aspirate or inhale food or saliva into their lungs. In fact, most people with ALS die of respiratory failure. The ability to think, see, hear, smell, taste and touch, however, usually is not affected.

Reviewed by health care specialists at UCSF Medical Center.