Myasthenia gravis (MG) is an autoimmune disease that causes periods of muscle weakness. It works by keeping your nerves from passing signals to your muscles.
Myasthenia gravis happens most often in women ages 20 to 40, and men ages 50 to 80, but it can happen at any age. The most common form of MG is a chronic, autoimmune, neuromuscular disorder characterized by fluctuating weakness of the voluntary muscle groups.
In the U.S., it is estimated that 20 in 100,000 people have MG or approximately 36,000 to 60,000 cases. However, as myasthenia gravis often remains underdiagnosed, the prevalence is most likely higher.
What causes myasthenia gravis?
MG results from abnormal immune system activity. Individuals with other auto-immune diseases or an abnormal thymus gland are more likely to have MG. Physicians suspect there may be a combination of factors that trigger the onset of MG symptoms in a susceptible indi...