What Is Multiple Sclerosis?
- Multiple sclerosis (MS) is a chronic disease that affects the central nervous system. MS is thought to be an autoimmune disease. In MS, the body’s immune system produces cells and proteins (antibodies) that attack myelin, a fatty substance that protects nerve fibers. The cause of MS is unknown. It is not an inherited disease, but it appears that genetic factors play a role in making some people more susceptible to developing it.
- MS affects significantly more women than men. Most patients first begin to have symptoms between the ages of 20 - 50.
- The course of MS varies among patients. The disease may be mild, moderate, or severe. Most patients have the relapsing-remitting form of MS in which flare-ups (also called relapses or exacerbations) of symptoms are followed by periods of remission.
- Symptoms of MS include fatigue; vision problems; difficulty walking; muscle weakness, stiffness, and spasms; bladder and bowel problems. Not all patients experience all symptoms.
Patients with multiple sclerosis are treated with medications and rehabilitation. Six disease-modifying drugs are approved to treat multiple sclerosis. These drugs can help reduce the frequency and severity of relapses and slow disease progression and disability. The FDA-approved drugs are:
- Interferon beta-1b (Betaseron, Extavia)
- Interferon beta-1a (Avonex)
- Interferon beta-1a (Rebif)
- Glatiramer acetate (Copaxone)
- Natalizumab (Tysabri)
- Mitoxantrone (Novantrone)
In 2010, the FDA approved two drugs that may help treat some of the specific symptoms associated with MS:
- Dalfampridine (Ampyra) is approved to improve walking in patients with MS. In clinical trials, patients treated with dalfampridine had faster walking speeds than patients who received placebo. Dalfampridine is taken as a pill.
- Onabotulinumtoxin A (Botox) is approved to treat upper limb spasticity in the flexor muscles of the elbow, wrist, and fingers. It is given by injection.
Review Date: 06/17/2010
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.