When lesions develop on your brain or spinal cord, they can disrupt the movement of signals along your nerves. This can cause a variety of symptoms.

For example, lesions may cause:

  • vision problems
  • muscle weakness, stiffness, and spasms
  • numbness or tingling in your face, trunk, arms, or legs
  • loss of coordination and balance
  • trouble controlling your bladder
  • persistent dizziness

Over time, MS can cause new lesions to form. Existing lesions may also grow larger. This might cause a relapse or acute flare of symptoms. This happens when your symptoms get worse or new symptoms develop.

It’s also possible to develop lesions without noticeable symptoms. Only 1 in 10 lesions causes outward effects, reports the National Institute of Neurological Disorders and Stroke (NINDS).

To help slow the progression of MS, many treatments are available. Early diagnosis and treatment might help prevent the development of new lesions.

To diagnose and monitor the progression of MS, your doctor will likely order imaging tests. These tests are called magnetic resonance imaging (MRI) scans. Doctors also use physical examinations to monitor the course of your MS.

MRI scans can be used to create pictures of your brain and spinal cord. This allows your doctor to check for new and changing lesions.

Tracking the development of lesions can help your doctor learn how your condition is progressing. If you have new or enlarged lesions, it’s a sign that the disease is active.

Monitoring lesions can also help your doctor learn how well your treatment plan is working. If you develop new symptoms or lesions, they might recommend changes to your treatment plan.

Your doctor can help you make decisions about your treatment options. They can also inform you about new therapies that might benefit you.

Many medications are available to treat MS. Some of those medications may help relieve your symptoms during a relapse or flare. Others may help slow the progression of the disease.

The U.S. Federal Drug Administration (FDA) has approved more than a dozen disease- modifying therapies (DMTs) to help slow the development of MS.

Most DMTs have been developed to treat relapsing forms of MS. However, some of them are used to treat other types of MS.

Many DMTs have shown promise for preventing new lesions in people with MS. For example, the following medications may help prevent lesions:

  • rituximab
  • ocrelizumab
  • daclizumab
  • alemtuzumab
  • cladribine
  • laquinimod
  • teriflunamide
  • fumaric acid
  • ozanimod

According to NINDS, clinical trials are underway to learn more about the potential benefits and risks of using these medications. Some of them are experimental, while others have been approved by the FDA.

In addition to slowing the growth of lesions, it might be possible to one day heal them.

Scientists are working to develop myelin-repair strategies, or remyelination therapies, that might help regrow myelin.

For example, a small clinical trial recently found that clemastine fumarate might help promote myelin repair in people with optic nerve damage from MS. Clemastine fumarate is an over-the-counter (OTC) antihistamine that’s used to treat seasonal allergies.

More research is needed to assess the potential benefits and risks of using this medication to treat MS. Research is also underway to identify and test other potential strategies for promoting remyelination.

MS can cause lesions to develop on the brain and spinal cord, which may lead to a variety of symptoms. To help slow the development of lesions and manage symptoms they might cause, your doctor may prescribe one or more treatments.

Many experimental therapies are also being developed not only to slow the growth of lesions, but also to heal them.