Multiple Sclerosis Overview

Multiple sclerosis (MS) is a chronic condition of the central nervous system that causes damage to the protective covering around nerve fibers, disrupting communication between the brain, spinal cord, and the rest of the body. Symptoms and progression can vary greatly from person to person, and while an exact cause is unknown, numerous disease-modifying therapies and symptom-management treatments are available to help individuals maintain their quality of life.

See MSAA’s Glossary of MS Terms for additional information.

MS Overview - IntroductionAn Introduction to Multiple Sclerosis

MS is an unpredictable disorder that can cause a variety of symptoms, which for many, can flare up and then subside over the course of days, months, or even years. Most individuals with MS are able to live a full and productive life, with much hope for the future. Read More

MS Overview - HistoryHistory of MS

Since the late 1300s, individuals with a progressive illness suggestive of MS have been observed. It wasn’t until 1868 that the famous neurologist, Jean-Martin Charcot, lectured on the features of MS and gave it a name. Read More

MS Overview - How MS Affects the BodyHow MS Affects the Body

Multiple sclerosis is a disease of the central nervous system. With MS, areas of the central nervous system become inflamed, damaging the protective covering (known as myelin) that surrounds and insulates the nerves (known as axons). Read More

MS Overview - Who Gets MSWho Gets MS

Most people with MS are diagnosed between the ages of 20 and 50, although individuals of any age may be diagnosed. More women are diagnosed with MS than men, and the area where someone lives, as well as race and ethnic background, also helps to determine one’s risk of developing the disease. Read More

MS Overview - Types of MSTypes of MS

The three most common forms of multiple sclerosis are relapsing-remitting MS, secondary-progressive MS, and primary-progressive MS. While most individuals with MS are initially diagnosed with one of the three main types of MS, other types of MS do occur. Read More

MS Overview - RelapsesMS Relapses

Relapses, also referred to as exacerbations, attacks, flare-ups, episodes, or bouts, are initially experienced by most people diagnosed with MS. Relapses occur with relapsing-remitting, progressive-relapsing, and sometimes secondary-progressive forms of MS. Read More

MS Overview - How MS Affects the Immune SystemHow MS Affects the Immune System

With multiple sclerosis, the body’s immune system malfunctions. It sends disease-fighting cells into the central nervous system that may destroy the body’s own myelin – a fatty-rich protein that serves as a protective covering, which insulates the nerve fibers. Read More

MS Overview - Possible Causes of MSPossible Causes of MS

Despite decades of research, the exact cause of multiple sclerosis remains undetermined. However, a combination of factors appears to be involved, and researchers have identified a number of these factors. Read More

MS Overview - Diagnosing MS and Evaluating Disease ActivityDiagnosing MS and Evaluating Disease Activity

Diagnosing and evaluating MS disease activity is typically done by neurologists through a neurological history and examination. In addition, tests that can indicate MS and rule out “MS mimickers” – such as MRI or lumbar punctures – are also performed. Read More

MS Overview - Additional Evaluative ToolsAdditional Evaluative Tools for MS

Measuring disease activity through other tools can help to evaluate disease progression, as well as changes in specific symptoms, such as fatigue, strength, mobility, vision, cognition, and others. Read More

MS Overview - The Importance of Disease-Modifying TherapiesThe Importance of Disease-Modifying Therapies for MS

Treatment with a disease-modifying therapy (DMT) is crucial for most individuals with MS, since disease activity and damage continues within the CNS even when no new symptoms are present. Read More

MS Overview - The Future of MS Research and TreatmentsThe Future of MS Research and Treatments

Since 1993, when the first disease-modifying therapy (DMT) for multiple sclerosis was approved, research into the disease process and its potential treatments has been both prolific and revealing. Read More

Last Updated: November 11, 2026