MS refers to multiple sclerosis, an inflammatory demyelinating disease of the nervous system that primarily involves the brain, cerebellum, brainstem, white matter of the spinal cord, and optic nerves. The cause of MS is not fully understood, but there is a genetic correlation. Some patients have a family history of MS, and if their parents have MS, the patients themselves are more likely to develop the disease than the general population, but not necessarily. Viral infection is a more common trigger, especially in relapsing-remitting MS, often after a cold, fever or diarrhea, which induces an exacerbation of symptoms. In addition, consideration of environmental factors is directly related to latitudinal factors. For example, Caucasians in high latitudes are far more likely to develop the disease than yellow populations in low latitudes. Treatment is with glucocorticoids or immunosuppressants. In the acute phase, high-dose hormone shock therapy is required, commonly methylprednisolone, and gammaglobulin can be used as an alternative. In the remission phase, immunosuppressive agents are used, as well as gamma-interferon, the effectiveness of which is not yet conclusive. Long-term hormone maintenance is required, and if combined with immunosuppressive agents, the hormone can be reduced appropriately.