Myasthenia Gravis

What is Myasthenia Gravis?

Myasthenia gravis is a rare, chronic autoimmune disease. Autoimmune means that the body’s immune system cannot tell the difference between healthy cells and invaders like viruses, fungi, or bacteria. Because it cannot tell the difference, the body begins to attack and damage healthy cells. Chronic means that it lasts for a long time or never goes away completely. With myasthenia gravis (MG), the body attacks areas where nerves communicate with muscles. This communication is what makes muscles work. Without the ability to communicate properly, the muscles become weak and tire easily.(1)

Other condition names

  • Acquired myasthenia
  • Autoimmune myasthenia gravis

Inheritance type

Multigenic/multifactorial, Not applicable


  • Europe: 1-5 in 10,000
  • Worldwide: 1-9 in 100,000
  • United States: 1-5 in 10,000

Age of Onset

  • All ages

  1. Myasthenia Gravis Fact Sheet. National Institute of Neurological Disorders and Stroke. Available at Accessed 12/8/2022.

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