Myasthenia Gravis

Myasthenia gravis (MG) is a chronic neuromuscular disease characterized by varying degrees of weakness of the skeletal or voluntary muscles of the body. The muscle weakness increases during periods of activity and improves after periods of rest.

MG most commonly occurs in young adult women and older men but can occur at any age. Although MG may affect any voluntary muscle, certain muscles including those that control eye movements, eye lids, chewing, swallowing, coughing, and facial expressions are more often affected.

Weakness may also occur in the muscles that control breathing and arm and leg movements. The muscles involved in MG vary from one individual to the next.

Today, MG is well-controlled. Therapies include medications such as anticholinesterase agents, prednisone, cyclosporine, and azathioprine; thymectomy, which is the surgical removal of the thymus gland; plasmapheresis, a procedure in which abnormal antibodies are removed from blood plasma; and high-dose intravenous immunoglobulin that modifies the immune system.

A physician will determine which treatment option is best for each patient depending on the severity of the weakness, which muscles are affected, and the patient’s age and other associated medical problems.

With treatment, most MG patients will have excellent improvement of their muscle weakness. In some patients, MG may go into remission and muscle weakness may disappear completely. In a few cases, MG may cause severe weakness resulting in acute respiratory failure; however, most patients can expect to lead normal or nearly normal lives.

Information provided by the
National Institute of Neurological Disorders and Stroke,
National Institutes of Health

Each year, Medical College of Wisconsin physicians care for more than 180,000 patients, representing nearly 500,000 patient visits. Medical College physicians practice at Children's Hospital of Wisconsin, Froedtert Memorial Lutheran Hospital, the Milwaukee VA Medical Center, and many other hospitals and clinics in Milwaukee and southeastern Wisconsin.