Relapsing-remitting MS (RRMS) is characterized by clearly defined attacks — called relapses or exacerbations — during which new or worsening neurological symptoms appear, followed by periods of partial or complete recovery (remission). It is the most common course of MS at the time of diagnosis, affecting roughly 85 percent of people newly diagnosed.
What is relapsing-remitting ms?
In relapsing-remitting MS, the immune system periodically attacks myelin — the protective coating around nerve fibers in the brain and spinal cord — causing inflammation that temporarily disrupts nerve signals. This produces a relapse: a period of days to weeks during which symptoms such as vision changes, numbness, weakness, or balance problems may appear or worsen. When the inflammation calms, some or all of the myelin can repair, and symptoms improve or resolve during remission.
During remission, the disease is not causing new damage that you can feel, but underlying inflammation and some level of injury may still be occurring silently on MRI scans. This is why treatment is usually recommended even when someone feels well — disease-modifying therapies are designed to reduce the frequency and severity of relapses and slow the accumulation of lesions visible on MRI.
Over time, without effective treatment, repeated attacks can leave behind permanent nerve damage that does not fully heal. Many people with RRMS eventually transition to a secondary-progressive phase, where disability accumulates more gradually without clear relapses. Modern disease-modifying therapies have dramatically changed this picture; many people treated early maintain good function for decades. The key is working closely with a neurologist who specializes in MS to find the right therapy and monitor disease activity.
Why it matters
Understanding that RRMS involves both visible episodes (relapses) and invisible ongoing activity (silent lesions) helps explain why continuing treatment during remission matters, even when you feel well. Regular MRI monitoring allows your care team to assess whether therapy is working and adjust the plan if needed.
The good news is that the treatment landscape for RRMS has expanded dramatically since the early 1990s. Dozens of approved disease-modifying therapies now exist, ranging from once-daily pills to periodic infusions, with varying profiles of effectiveness and side effects. More options mean more ability to tailor treatment to your individual situation, lifestyle, and goals.
Related terms
Related articles
Medical disclaimer