Types of MS Choices booklet

Everyone who has a diagnosis of multiple sclerosis (MS), will be different. Even those with the same type of multiple sclerosis will experience it very differently. There are so many symptoms of MS, and they affect everyone in a variety of ways. No two people are the same.

There are three main broad groups into which MS is categorised and we will explore these more throughout the booklet.

Relapsing remitting MS

The majority of people with MS are diagnosed as having the relapsing remitting form – perhaps as many as 85 percent. People with relapsing remitting MS (RRMS) experience relapses periodically – often months or years apart. When a relapse resolves, the person moves into remission, hence ‘relapsing-remitting’.

The severity and type of relapse can vary between people, but may also vary for an individual – affecting vision or mobility, or causing pain. New symptoms can appear, or symptoms experienced previously may worsen.

It can often be difficult to determine if you are having a relapse. It is important to let your GP and MS nurse know if you think you are experiencing a change in symptoms so they can determine if it is a clinical relapse and therefore if treatment is required.

Your MS nurse may advise steroid treatment to reduce inflammation in the body and to help aid recovery from a relapse.

The National Institution for Health and Care Excellence (NICE) published guidelines in June 2022 for the management of MS. In these guidelines a relapse can be diagnosed if the person with MS has

  • developed new symptoms
  • or has a worsening of existing symptoms
  • and these symptoms have lasted for more than 24 hours in the absence of infection or any other cause after a stable period of at least one month

Some people with RRMS are eligible for disease modifying therapies (DMTs), which can reduce the number of relapses. There are a number of different types of DMT available depending on if you are eligible and fit the criteria. Talk to your neurologist or MS nurse about what DMT you may be eligible for.

There are other sub-categories of RRMS used by neurologists, these can include the following

Benign MS

A person will initially be diagnosed with RRMS and it is only after several years of living with a mild form of RRMS, that a neurologist may suggest that their MS is benign.

Studies show that people with benign MS (BMS) will have little or no disability, equal to two or three on the Expanded Disability Status Scale (EDSS), at ten years after onset.

A person with BMS can still experience relapses and symptoms, and their MS may change as they grow older.

Rapidly evolving severe relapsing remitting MS

Also called highly active or severe RRMS, rapidly evolving severe RRMS (RES-RRMS) is categorised as having two disabling relapses in one year, as well as new MS activity in the brain showing up as lesions on an MRI.

People with rapidly evolving severe RRMS may be eligible for treatment with a DMT. Talk to your neurologist or MS nurse about the DMTs you may be eligible for.

Secondary progressive MS

People who are initially diagnosed with relapsing remitting MS (RRMS) may then, in the future, transition to secondary progressive MS (SPMS).

Secondary progressive MS is characterised by fewer or no relapses and a gradual worsening of symptoms.

Some people with SPMS may still experience relapses, but remission following a relapse is less complete, or there is less time between relapses.

Only a neurologist can diagnose SPMS after careful observation of MS symptoms over time. A small number of people are diagnosed with SPMS from the outset. This is because looking back it becomes apparent that the person has experienced MS relapses for a number of years prior to seeing a neurologist.

Around two-thirds of people diagnosed with RRMS will develop SPMS. SPMS varies between individuals with some people experiencing a gradual worsening of symptoms, and others becoming more disabled more quickly.

There are many medications, complementary therapies and strategies to manage the symptoms of SPMS.

There is one main DMT licensed specifically for people with active SPMS. Meaning, people who continue to experience relapses or are showing MS activity on a magnetic resonance imaging (MRI) scan. A few other DMTs can be prescribed for SPMS, if you are still experiencing relapses. Talk to your neurologist or MS nurse about the DMTs you may be eligible for.

Primary progressive MS

Around ten to fifteen per cent of people are diagnosed with primary progressive MS (PPMS). PPMS begins with a slow progression of neurological symptoms. Some people with PPMS experience a steady worsening of symptoms, and others find they become disabled more quickly.

PPMS is mostly diagnosed in people over 40 years. It can take many months or years for a neurologist to arrive at a definitive diagnosis of PPMS as changes can be subtle over an extended time. It is commonly a diagnosis of exclusion before reaching the point of confirming PPMS officially.

Most people with PPMS will not have relapses, but a few do. If relapses are part of your PPMS, your neurologist may use the sub-category ‘progressive relapsing MS’.

Definitions make explaining my MS to people much easier.

Progressive relapsing MS

Around five per cent of people affected by MS have the progressive relapsing form (PRMS).

A person will have progressive symptoms that continue to worsen over time at varying rates depending on the individual. A relapse in PRMS is an exacerbation of symptoms that have already been occurring.


Clinically Isolated Syndrome

Although not technically a classification of MS, it is important to include this within this booklet. Clinically Isolated Syndrome (CIS) is used to describe the first neurologic episode that lasts at least 24 hours and is caused by inflammation or demyelination in one or more sites in the central nervous system. CIS is diagnosed before a formal diagnosis of MS can be made. Around 60 – 80 per cent of people with CIS, who present with brain lesions, will go on to develop MS within ten years.

Those with CIS who show abnormalities on MRI scans within one year, may be offered treatment with a disease modifying therapy (DMT).

Advanced MS

This terminology is used when MS has progressed and is having a greater impact, with significant physical symptoms or cognitive impairment that does not improve. This is most typical in the later stages of SPMS or PPMS. A person is more highly affected by their symptoms and requires additional support from carers and/or family members.

The term Advanced MS is not about the type of MS a person has, but rather about the level of impact and difficulties MS is causing.

The level of impact of these symptoms means they can be complex and difficult to treat. A person living with advanced MS is still entitled to an annual neurology review and may need referrals to a wider variety of health professionals in order to find the best ways to manage symptoms and maintain a good quality of life.

Further information

MS-UK Choices booklets
Disease modifying therapies, What is MS?, Is it MS?, Diagnosis, Complementary and other therapies, Diet and supplements