Myasthenia gravis is characterized by weakness and rapid fatigue of any of the voluntary muscles, typically when the muscles are being used. Myasthenia gravis is caused by an autoimmune response to the affected areas, disrupting the normal communication at the neuromuscular junction (the connection between the nerve and the muscle) and rendering the patient weak.
Signs and symptoms of myasthenia gravis are weakness of arm or leg muscles, double vision, drooping eyelids, and difficulties with speech, chewing, swallowing and breathing. There is no cure for myasthenia gravis. However, there are many treatments designed to help acutely when a patient is in Omyasthenic crisis, and to keep patients feeling well for long periods of time. Treatments are geared towards alleviating the symptoms and reducing the body's immune attack on the acetylcholine receptor.
While myasthenia gravis can affect people of any age, it's most common in women younger than 40 and in men older than 60. Myasthenia gravis occurs in two or three people per 10,000.