Overview

What happens when you have multiple sclerosis (MS)?

Generally, MS follows one of four courses:

• Relapsing-remitting. Symptoms fade and then return off and on for many years.
• Secondary progressive. At first it follows a relapsing-remitting course. And then it becomes steadily worse (progressive).
• Primary progressive. It is progressive from the start.
• Clinically isolated syndrome. The symptoms last for 24 hours or longer and go away.

For most people, MS follows a relapsing-remitting course, at least at first. It involves a series of attacks that cause symptoms. These are called relapses, flares, or exacerbations. They may last for days or weeks and then partly or completely go away.

Relapses may be mild or severe and tend to recur over a period of years. They may become worse and more frequent over time. As time goes by, symptoms may linger after each relapse, and new symptoms often develop.

Most people live with MS for decades. Many become more disabled as they get older.