If you’re having relapses (flare-ups) more often — or if those flares leave you feeling much worse than before — you may need stronger treatment for your multiple sclerosis (MS).

Fortunately, there are several MS medications that are called highly effective disease-modifying therapies (HE DMTs) because they work so well to slow disease activity and reduce the progression of disability. Experts have determined that people with highly active MS should start HE DMTs earlier to reduce the impact of MS on their lives.

So, how do you know when it might be time for advanced treatment for MS? Below are five key advanced MS symptoms that can signal that your MS is highly active. We’ll also go over what tests your doctor might run to confirm this. Knowing these signs can help you get the treatment you need sooner.

5 Signs Your MS May Be Highly Active

There is no single definition of highly active multiple sclerosis. Instead, your neurologist looks at your test results and symptoms of MS to understand your disease activity. If you’ve noticed any of the following symptoms, it may be time to make an appointment.

1. You’re Having a Hard Time Recovering From a Flare

If you’re struggling to feel better after a relapse (also called a flare, attack, or exacerbation), it may be a sign that your MS is highly active. Your body is trying to recover from the spike of inflammation, which can affect both your physical and mental health.

You may still feel fatigue, leg weakness, numbness, or tingling that lasts longer than usual. Your cognitive function (ability to think and process information) can also be affected. If you’re not bouncing back from a flare as quickly as you used to, let your neurologist know. They may use tools like walking tests, magnetic resonance imaging (MRI) scans, and disability scales to see how much the flare is affecting you.

2. There’s Less Time Between Your Flares

When MS is well managed with medication, relapses are less common. If you’ve had two or more flares in the past year, it might mean that your multiple sclerosis is highly active— especially if you’re taking a DMT consistently as prescribed.

If you’ve had two or more MS relapses within the past year, it might be a sign that your MS is highly active.

According to the National Multiple Sclerosis Society, a multiple sclerosis flare happens when new symptoms appear or old symptoms get worse. A true flare lasts at least 24 hours and happens at least 30 days after the last one. Keep track of when your flares begin and end and what symptoms you notice.

If you’re not sure whether you’re in a flare or if you’re fully recovered, talk to your neurologist. They can look at how often you have flares to help diagnose highly active MS.

3. You Have Trouble Balancing and Walking

Ataxia is an MS symptom in which nerve damage affects your muscle coordination. Ataxia symptoms show up differently depending on which area of your brain has been affected. For example, your cerebellum is responsible for coordinating movements. If you feel more off-balance or clumsy, or if your gait (how you walk) has changed — especially if this came on suddenly— it may be a sign of highly active MS.

4. You’re Having More Muscle Spasms and Tremors

MS can also cause tremors or uncontrollable shaking that affects your arms or legs or even your vocal cords. You may notice your arms and legs shake while reaching for something or even when you’re resting in bed.

Vocal cord spasms can interfere with your speech. You may speak more quietly, slur your words, or pause more while you’re talking. Pay attention to whether these symptoms are getting worse after a flare.

5. You’re Struggling To Control Your Bowels

Your bowels and anus are controlled by a series of muscle movements. Losing of control of the sphincter muscle that opens and closes the anus is a sign of highly active MS. This can lead to bowel leakage or incontinence. If you’re having trouble controlling your bowel movements, or if you can’t always sense when one is coming, let your neurologist know.

How Does Your Doctor Determine if MS Is Highly Active?

Your doctor or neurologist may use different tests to see if your MS is highly active, which we discuss in more detail below.

Checking for New Lesions

MS is an autoimmune disease that causes your immune system to attack your central nervous system (CNS). The CNS includes the brain, spinal cord, and optic nerves. In MS, the immune system specifically attacks myelin, the fatty layer that protects your axons (nerve fibers). This damage creates lesions on your brain and spinal cord that interfere with nerve signals.

Your doctor may order MRI scans and use the EDSS to assess your disability to find out whether your MS is highly active.

Your neurologist may use imaging tests like MRI scans, sometimes with a contrast dye called gadolinium, to look for any new lesions that are 3 millimeters or larger. Having three or more new lesions show up on two MRI scans taken six to 12 months apart is a sign of highly active MS.

Assessing Disability

The Expanded Disability Status Scale (EDSS) measures disability with MS and how it changes over time. The scale ranges from 0 to 10 — with 0 meaning no disability and 10 meaning death from MS.

According to the Consortium of Multiple Sclerosis Centers (CMSC), you may be more likely to have highly active MS if:

• You reach an EDSS score of 4 within five years of your first MS symptoms.
• Your EDSS score changes by two or more points within one year.
• Your EDSS score changes in a way that leads to new disability.

Other Risk Factors for Highly Active MS

Some people are at greater risk for highly active MS, even though many of these risk factors are out of their control. According to the CMSC, you may be more likely to develop highly active MS if you:

• Are male
• Are African American
• Were diagnosed at age 40 or older

Having relapses is another risk factor for highly active MS. According to the CMSC, between 10 percent and 15 percent of people with relapsing MS develop highly active MS. Relapsing forms of MS include relapsing-remitting MS (RRMS), clinically isolated syndrome (CIS), and active secondary progressive MS (SPMS).

Highly Effective DMTs for Highly Active MS

Because MS is caused by an overactive immune system, many treatment options focus on calming or blocking immune activity. Highly effective disease-modifying therapies prevent immune cells from attacking your neurons in a few different ways.

If your MS is highly active, your neurologist may recommend you start taking a highly effective DMT to slow disease progression.

Some treatments target immune cells called lymphocytes, which drive inflammation. Others block a type of lymphocyte called B cells from making antibodies (immune proteins) that damage myelin.

Most experts consider highly effective DMTs for MS to include:

• Alemtuzumab (Lemtrada)
• Cladribine (Mavenclad)
• Natalizumab (Tysabri)
• Ocrelizumab (Ocrevus)
• Ofatumumab (Kesimpta)
• Rituximab (Rituxan)
• Ublituximab-xiiy (Briumvi)

Moderate-efficacy DMTs for MS include:

• Dimethyl fumarate (Tecfidera)
• Diroximel fumarate (Vumerity)
• Fingolimod (Gilenya)
• Monomethyl fumarate (Bafiertam)
• Ozanimod (Zeposia)
• Siponimod (Mayzent)

Some HE DMTs are given as subcutaneous injections (under the skin), while others are given by intravenous (IV) infusion at an MS infusion clinic or other medical facility. How often you need infusions varies depending on the medication.

One highly effective DMT and most moderate-efficacy DMTs are oral medications, which means you take them by mouth. Oral DMTs can be an alternative to traditional DMT infusions and injections.

Many people with MS qualify for financial assistance to cover the cost of HE DMTs and even infusion treatments.

Talk With Others Who Understand

On MyMSTeam, people share their experiences with MS, get advice, and find support from others who understand.

Have you and your health care provider discussed whether your MS is highly active? Are you currently taking a highly effective disease-modifying treatment? Let others know in the comments below.