Multiple sclerosis (MS) is a condition in which the insulating cover along the nerve cells is damaged. This damage disrupts the transmission of nerve signals, causing a variety of symptoms, including double vision, blindness in one eye, muscle weakness, and trouble with sensation or coordination. MS takes several forms, including relapsing MS (symptoms occur sporadically) and progressive MS (symptoms build up over time). In the relapsing MS, symptoms may disappear completely between attacks, although some permanent nerve problems often remain. While the cause of MS is unclear, the underlying problem is related to damage to the insulating layer of nerves (myelin sheath), possibly caused by the immune system.
There is still no cure for MS, but there are treatments for initial attacks, medications and therapies to improve symptoms, and recently developed drugs to slow the worsening of the disease. These new drugs have been shown to reduce the number and severity of relapses and to delay the long-term progression of MS. These treatments may include injectable steroids, oral steroids, and plasma exchange as a secondary option in certain types of MS.