Multiple sclerosis (MS) causes damage to nerve fibers in the central nervous system. Over time, it can lead to vision problems, muscle weakness, loss of balance or numbness. Several drug therapies can limit nerve damage and slow the disease’s progression.
Multiple sclerosis (MS) is an autoimmune disease. With these conditions, your immune system mistakenly attacks healthy cells. In people with MS, the immune system attacks cells in the myelin, the protective sheath that surrounds nerves in the brain and spinal cord.
Damage to the myelin sheath interrupts nerve signals from your brain to other parts of your body. The damage can lead to symptoms affecting your brain, spinal cord and eyes.
There are four types of multiple sclerosis:
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Nearly 1 million adults in the U.S. are living with multiple sclerosis. MS commonly affects more women than men. Most people with MS receive a diagnosis between the ages of 20 and 40.
Experts still don’t know for sure what causes multiple sclerosis. Research is ongoing to help identify what causes the disease. Factors that may trigger MS include:
Vision problems — such as optic neuritis (blurriness and pain in one eye) — are often one of the first signs of multiple sclerosis. Other common symptoms include:
If MS progresses, worsening symptoms may lead to complications such as:
Many conditions could cause similar neurological symptoms. Getting an accurate diagnosis is sometimes difficult. Some people see multiple providers over years before receiving a diagnosis. While the search can be frustrating, it’s important to keep looking for answers. Identifying and treating MS as soon as possible can help slow the disease’s progression.
If your primary care provider suspects you may have MS, you will need to see a neurologist. A neurologist is a doctor who specializes in treating conditions that affect the nervous system, which includes your brain and spinal cord.
No one test can provide a definitive MS diagnosis. To understand what’s causing symptoms, your healthcare provider will do a physical exam. You may also have blood tests and imaging tests, such as MRI. An MRI looks for evidence of lesions (areas of damage) in the brain or spinal cord that indicate multiple sclerosis. Lesions develop as a result of damage to the myelin sheath surrounding the nerves. A spinal tap (lumbar puncture) may also need to be done.
If these tests don’t provide a clear answer, your neurologist may recommend an evoked potentials test. This test checks your nerve function by measuring electrical activity in the brain and spinal cord.
There is currently no cure for MS. Treatment focuses on managing symptoms, reducing relapses (periods when symptoms worsen) and slowing the disease’s progression. Your comprehensive treatment plan may include:
Disease-modifying therapies are the most effective way to reduce the number of flare-ups (also called relapses or attacks) you experience. Leading a healthy lifestyle is also important. The choices you make can help slow disease progression. Good care can also lessen your symptoms and improve your quality of life.
Lifestyle changes that can improve your condition include:
In some cases, multiple sclerosis does lead to disability and loss of some physical or mental function. But thanks to advances in treatment, most people with MS will continue to lead full, active and productive lives. Taking steps to manage your health and lifestyle can help improve your long-term outcome.
Depression is very common in people with multiple sclerosis (MS). In fact, symptoms of depression severe enough to require medical intervention affect up to half of all people with MS at some point during their illness.
Depression may be the result of a difficult situation or stress. It is easy to understand how having MS, with its potential for progressing to permanent disability, can bring on depression.
Depression might be actually caused by MS. MS may affect the insulating myelin that surrounds nerves which transmit signals affecting mood.
Depression is also a side effect of some drugs used to treat MS, such as steroids or interferon.
Heat or high humidity can cause many people with MS to experience a temporary worsening of their symptoms. Doctors believe that this occurs because heat causes nerves (whose myelin covering has been removed by MS) to conduct electrical signals even less efficiently.
For reasons that are not well understood, extremely cold temperatures and changes in temperature can also cause MS symptoms, usually spasticity (muscle stiffness), to flare.
You should call your healthcare provider if you experience:
You may want to ask your healthcare provider:
A note from Cleveland Clinic
Multiple sclerosis is a disease that affects the central nervous system (brain, spinal cord and optic nerves). It is an autoimmune disease that causes your immune cells to mistakenly attack your healthy nerve cells. These attacks lead to inflammation and damage to the myelin sheath that covers and protects your nerve cells. This damage causes neurological symptoms — such as loss of balance, vision problems and muscle weakness. Several effective treatments exist for MS. These medications reduce relapses and help slow the progression of the disease. Most people with MS are able to manage their symptoms and lead full, active lives.
Last reviewed by a Cleveland Clinic medical professional on 02/10/2021.
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