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 MS 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 MS, 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 MS 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, MS can produce partial or complete paralysis.
Most people with MS 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 MS have hearing loss. Approximately half of all people with MS 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 MS.
Currently there is no cure for MS. Many individuals do well with no therapy at all, especially since many medications have serious side effects and some carry significant risks.
Steroid drugs may be prescribed to treat acute symptoms of an attack, such as inflammation; they do not affect the course of the disease over time. Several drugs have been approved by the U.S. Food and Drug Administration (FDA) to treat one or more forms of multiple sclerosis, either by decreasing attack frequency and severity, treating relapses, or delaying disease progression. Some drugs are taken intravenously, some by infusion, and some oral.
All drugs should be prescribed and closely monitored by specially trained physicians, as some medications have serious side effects. In March 2019 the FDA approved siponimod tablets taken orally by adults to treat relapsing- forms of MS.
Beta interferon drugs have been shown to reduce the number of relapses (exacerbations) and may slow the progression of disease. FDA-approved beta interferon drugs for MS include Avonex, Betaseron, Extavia, and Refib. Monoclonal antibody drugs are designed to alter the immune system response to inflammation. Approved drugs include Ocrevus, Lemtrada, and Tysabri.
Other drugs approved include Copaxone, Gilenya, Aubagio, and Tecfidera, all of which address relapsng forms of MS. An immunosuppressant treatment, Novantrone, is approved for the treatment of advanced or chronic MA. Ampyra can improve walking in individuals with MS.
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 individuals may find that various aids—such as foot braces, canes, and walkers—can help them remain independent and mobile.
Avoiding excessive activity and avoiding heat are probably the most important measures patients can take to counter physiological fatigue.
If psychological symptoms of fatigue such as depression or apathy are evident, antidepressant medications may help.
Other drugs that may reduce fatigue in some, but not all, patients include Symmetrel and Cylert.
Although improvement of optic symptoms usually occurs even without treatment, a short course of treatment with intravenous methylprednisolone (Solu-Medrol) followed by treatment with oral steroids is sometimes used.
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.
Scientists at the National Institute of Neurological Disorders and Stroke and elsewhere continue their extensive efforts to create new and better therapies for MS.
One of the most promising MS research areas involves naturally occurring antiviral proteins known as interferons. Beta interferon has been shown to reduce the number of exacerbations and may slow the progression of physical disability. When attacks do occur, they tend to be shorter and less severe.
In addition, there are a number of treatments under investigation that may curtail attacks or improve function.
Over a dozen clinical trials testing potential therapies are underway, and additional new treatments are being devised and tested in animal models.