An unpredictable disease of the central nervous system, multiple sclerosis (MS) can range from relatively benign to somewhat disabling to devastating, as communication between the brain and other parts of the body is disrupted. Many investigators believe Multiple Sclerosis to be an autoimmune disease -- one in which the body, through its immune system, launches a defensive attack against its own tissues. In the case of Multiple Sclerosis, it is the nerve-insulating myelin that comes under assault. Such assaults may be linked to an unknown environmental trigger, perhaps a virus.

Most people experience their first symptoms of Multiple Sclerosis between the ages of 20 and 40; the initial symptom of MS is often blurred or double vision, red-green color distortion, or even blindness in one eye. Most MS patients experience muscle weakness in their extremities and difficulty with coordination and balance. These symptoms may be severe enough to impair walking or even standing. In the worst cases, Multiple Sclerosis can produce partial or complete paralysis. Most people with Multiple Sclerosis also exhibit paresthesias, transitory abnormal sensory feelings such as numbness, prickling, or "pins and needles" sensations. Some may also experience pain. Speech impediments, tremors, and dizziness are other frequent complaints. Occasionally, people with Multiple Sclerosis have hearing loss. Approximately half of all people with Multiple Sclerosis experience cognitive impairments such as difficulties with concentration, attention, memory, and poor judgment, but such symptoms are usually mild and are frequently overlooked. Depression is another common feature of Multiple Sclerosis.

There is as yet no cure for Multiple Sclerosis. Many patients do well with no therapy at all, especially since many medications have serious side effects and some carry significant risks. In the past, the principal medications used to treat MS were steroids including adrenocorticotropic hormone (better known as ACTH), prednisone, prednisolone, methylprednisolone, betamethasone, and dexamethasone. While steroids do not affect the course of MS over time, they can reduce the duration and severity of attacks in some patients. Spasticity, which can occur either as a sustained stiffness caused by increased muscle tone or as spasms that come and go, is usually treated with muscle relaxants and tranquilizers such as baclofen, tizanidine, diazepam, clonazepam, and dantrolene. Physical therapy and exercise can help preserve remaining function, and patients may find that various aids -- such as foot braces, canes, and walkers -- can help them remain independent and mobile. If psychological symptoms of fatigue such as depression or apathy are evident, antidepressant medications may help.

A physician may diagnose MS in some patients soon after the onset of the illness. In others, however, doctors may not be able to readily identify the cause of the symptoms, leading to years of uncertainty and multiple diagnoses punctuated by baffling symptoms that mysteriously wax and wane. The vast majority of patients are mildly affected, but in the worst cases, MS can render a person unable to write, speak, or walk. MS is a disease with a natural tendency to remit spontaneously, for which there is no universally effective treatment.

National Institute of Neurological Disorders and Stroke