When the muscles necessary for breathing are affected, a patient is said to be in myasthenic crisis.

Myasthenic crisis often occurs when you develop a severe infection, so you'll probably need to be treated with antibiotics as well.

In myasthenic crisis a paralysis of the respiratory muscles occurs, necessitating assisted ventilation to sustain life.

If the myasthenia is serious (myasthenic crisis), plasmapheresis can be used to remove the putative antibodies from the circulation.

In addition, in about 10 percent of cases, affected individuals may develop potentially life-threatening complications due to severe involvement of muscles used during breathing (myasthenic crisis).

In myasthenic crisis, where a person is not able to produce enough nicotinic acetylcholine receptor stimulation, edrophonium will reduce the muscle weakness by effectively supplying more acetylcholine.