What Is Multiple Sclerosis?

Medically Reviewed by Christopher Melinosky, MD on June 29, 2020

Multiple sclerosis, or MS, is a long-lasting disease that can affect your brain, spinal cord, and the optic nerves in your eyes. It can cause problems with vision, balance, muscle control, and other basic body functions.

The effects are often different for everyone who has the disease. Some people have mild symptoms and don’t need treatment. Others will have trouble getting around and doing daily tasks.

MS happens when your immune system attacks a fatty material called myelin, which wraps around your nerve fibers to protect them. Without this outer shell, your nerves become damaged. Scar tissue may form.

The damage means your brain can’t send signals through your body correctly. Your nerves also don’t work as they should to help you move and feel. As a result, you may have symptoms like:

The first symptoms often start between ages 20 and 40. Most people with MS have attacks, also called relapses, when the condition gets noticeably worse. They’re usually followed by times of recovery when symptoms improve. For other people, the disease continues to get worse over time.

In recent years, scientists have found many new treatments that can often help prevent relapses and slow the disease’s effects.

What Causes MS?

Doctors don’t know for sure what causes MS, but there are many things that seem to make the disease more likely. People with certain genes may have higher chances of getting it. Smoking also may raise the risk.

Some people may get MS after they’ve had a viral infection -- like the Epstein-Barr virus or the human herpesvirus 6 -- that makes their immune system stop working normally. The infection may trigger the disease or cause relapses. Scientists are studying the link between viruses and MS, but they don’t have a clear answer yet.

Some studies suggest that vitamin D, which you can get from sunlight, may strengthen your immune system and protect you from MS. Some people with higher chances of getting the disease who move to sunnier regions seem to lower their risk.

Getting a Diagnosis

It can be hard to diagnose MS, since its symptoms can be the same as many other nerve disorders. If your doctor thinks you have it, they’ll want you to see a specialist who treats the brain and nervous system, called a neurologist. They’ll ask you about your medical history and check you for key signs of nerve damage in your brain, spinal cord, and optic nerves.

There’s no single test that can prove you have MS. Your doctor will use a few different ones to check you. These may include:

  • Blood tests to rule out diseases that cause similar symptoms, like Lyme disease and AIDS.
  • Checks of your balance, coordination, vision, and other functions to see how well your nerves are working.
  • A test that makes detailed pictures of the structures in your body, called an MRI.
  • Analysis of the liquid that cushions your brain and spinal cord, called cerebrospinal fluid (CSF). People with MS usually have specific proteins in their CSF.
  • Tests (called evoked potentials) that measure the electrical activity in your brain.
  • OCT (Optical coherence tomography) used to detect changes in the retina which could warn of brain atrophy


There is no cure for MS right now, but a number of treatments can improve how you feel and keep your body working well.

Your doctor can also prescribe drugs that may slow the course of the disease, prevent or treat attacks, ease your symptoms, or help you manage the stress that can come with the condition.

Drugs that may slow your MS or help nerve damage include:

Your doctor may give you steroids to make your MS attacks shorter and less severe. You can also try other drugs, like muscle relaxants, tranquilizers, or botulinum toxin (Botox), to ease muscle spasms and treat some of the other symptoms.

A physical therapist can teach you exercises that will keep up your strength and balance and help you manage fatigue and pain. An occupational therapist can teach you new ways to do certain tasks to make it easier to work and take care of yourself. If you have trouble getting around, a cane, walker, or braces can help you walk more easily.

Along with treatment, you can do other things to ease your MS symptoms. Get regular exercise and avoid too much heat to boost your energy. Ask your doctor about trying yoga to ease fatigue or stress. Take care of your emotional health, too. It’s OK to ask family, friends, or a counselor for help with any stress or anxiety you may feel. Support groups are also great places to connect with other people living with MS.

What’s Your Outlook With MS?

Because there’s no cure for MS, your doctor will focus on treating your symptoms. Over the past 20 years, new treatments have greatly improved the quality of life for those with the disease. These treatments not only help with symptoms, they can also slow the progression of MS.

About half of those with MS will still be able to walk on their own 15 years after diagnosis. The rest will need a wheelchair or other aids. The average time to serious disability like confinement to bed is 33 years.

Most people with MS have close to a normal life expectancy. Though in some serious cases, people with MS can die early from pneumonia or other infections related to their disease, most people die from other ailments. Overall, the life expectancy of someone with MS is only about 5% less than a normal healthy adult.

In general, symptoms and disabilities don’t worsen significantly from those you have in the first 5 years after diagnosis. Still, it’s hard to know what path the disease will take in any particular case.

Careful and consistent monitoring and treatment of MS with your medical team is the best way to keep your symptoms at bay and slow the progression of the disease.

What’s Coming for MS Treatment?

Research is giving doctors more treatment options for the condition, a better idea of what causes it, and the ability to diagnose it earlier. Stem cell and genetic research may soon help doctors repair damaged nerves or stop the disease before it causes damage.

Scientists are also looking for new ways to treat MS in clinical trials. These trials test new drugs to see if they're safe and if they work. They're often a way for people to try new medicine that isn’t available to everyone. Ask your doctor if one of these trials might be a good fit for you.

Show Sources


National Multiple Sclerosis Society.

National Institute of Neurological Disorders and Stroke: “NINDS Multiple Sclerosis Information Page.”

MS Coalition: “Emerging Therapies Collaborative.”

MS International Federation: “Complementary and Alternative Therapies.” “Prognosis.”

University of Utah Medicine: “Multiple Sclerosis.”

British National Health Service: “Multiple Sclerosis.”

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