How to Spot the Signs of an MS Flare
When new multiple sclerosis symptoms crop up or old ones worsen, you may be having an MS relapse.


More than two-thirds of the approximately 1 million people with multiple sclerosis (MS) in the United States have relapsing-remitting MS (RRMS), which means they have periods when their symptoms are severe — relapses — and periods when their symptoms are less severe, although they may not disappear completely. Some people with secondary-progressive MS, a later stage of RRMS, continue to have relapses, along with a general progression of symptoms and disability.
Is It a Flare or a Pseudoexacerbation?
The periods when new symptoms appear or old ones reappear or get worse are called MS flares, or, alternatively, relapses, attacks, or exacerbations. Flares occur because of inflammation in the central nervous system — the brain and spinal cord — causing damage to the myelin or underlying nerve fibers.
To be considered a true flare, a relapse must occur at least 30 days after the previous flare, and the new or recurring symptoms must last for at least 24 hours.
When new or worsened MS symptoms clear up in less than 24 hours, it’s called a pseudo-relapse or pseudoexacerbation. Heat, stress, fatigue, and infections are often behind pseudoexacerbations.
While the symptoms of a pseudoexacerbation are real, there is no new damage being done in the central nervous system.
True flares typically come on over several hours to several days and can last anywhere from a few days to a few weeks.
It is not always clear from the outset whether a person is experiencing a flare or a pseudoexacerbation, and sometimes watching and waiting is the only way to know.
But if you experience any new symptom that interferes with your ability to function normally, says Matthew McCoyd, MD, a neurologist at Loyola University Medical Center in Chicago, let your doctor know about it right away.
Symptoms of a Flare
The signs and symptoms of an impending MS flare include virtually any of the possible symptoms caused by MS. They vary from person to person and from flare to flare.
Many people begin to recognize certain symptoms that signal that a flare may be coming. “As unpredictable as the disease is, my signs are pretty regular,” says Cathy Chester, a writer who lives in New Jersey with her husband and son and was first diagnosed with relapsing-remitting MS in 1986.
“My feet and sometimes my fingers start tingling, and I begin to feel weak; those are usually the first signs that something is awry,” says Chester. For Chester, numbness and extra fatigue often follow those initial symptoms. “I know at that point that my body is warning me that a flare or a pseudoexacerbation is coming,” she says.
Other possible signs of an oncoming relapse include:
- Increased fatigue
- Tingling or numbness anywhere on the body
- Brain fog, or difficulty thinking
- Muscle spasms
- Depression
- Visual changes, such as blurring or double vision
- Pain
- Tremors
- Severe balance problems
- Severe weakness
- Dizziness
- Bladder changes
- Any combination of these symptoms
Getting to know how MS usually affects you, and monitoring how you feel from day to day, can help you catch potential flares early. At the same time, being overly vigilant can have a negative effect on your mental health.
It’s best — although not easy — to find a way to strike a balance between noticing what’s happening in your body and worrying about every change or sensation.
“When I was first diagnosed, I worried a lot more when I started to get these signals, partly because everything was new,” says Chester. Now that she’s more knowledgeable about living with MS, she adds, it’s become easier to notice symptoms or changes in her body and not overreact or get stressed about them.
It’s also important to consider other possible causes of your symptoms; they may have nothing to do with MS, but they may still need to be checked out by a medical professional.
Can MS Relapses Be Prevented?
MS flares may not be completely preventable, but the newer disease-modifying medications for MS have been shown to greatly reduce relapses. However, it can take a few tries to find the drug that works best for the individual.
Aside from medication, remaining calm and adopting a positive attitude whenever possible can help prevent a flare from coming on, says Chester. “Keeping your stress level at a minimum and taking care of yourself really does help,” she says.
“Listen to your body and reach out for support from friends and family. If you need something, ask,” says Chester.
Here are some common MS symptoms and a few self-care tips to manage them:
Have a plan to head off fatigue. MS fatigue is not like normal fatigue. It can be so severe that it's disabling. But “having good sleep habits, avoiding caffeine and too much alcohol, and getting some daily exercise are good ways to prevent MS fatigue,” says Dr. McCoyd. There are also medicines that help fight MS fatigue.
Find workarounds for brain fog. Slowed thinking, confusion, and difficulty concentrating are frequent but under-recognized MS symptoms. “It can be infuriating for me, because I’m a writer,” says Chester. “I have issues finding the right word that I want to use, or I can’t remember facts that I know by heart,” she says. Two strategies that can help you stay focused and remember things better are to avoid multitasking and to write things down. Cognitive rehabilitation can also help.
Get help for painful symptoms. “Even though I’ve had MS for over 30 years, I just experienced spasticity for the first time last year; I was surprised to have this new symptom,” says Chester. “I have spasms in my feet, my calves, and my hands, and it comes and goes,” she says. “It’s a strange feeling to watch your toes and fingers have a mind of their own,” she adds.
“It can be very painful; I didn’t want to add another medication, and so I use deep breathing and meditation to help with the pain,” says Chester. On the suggestion of her neurologist, Chester also began to drink water with electrolytes, and that’s helped, she says.
Take depression seriously. “Depression is common in MS and often goes unrecognized,” McCoyd says. “It is important for people with MS to have lots of support, exercise regularly, and use stress-reduction techniques like yoga or meditation to combat this MS symptom.” Seeking help from a mental health professional is also important when depression persists in spite of self-care efforts.
Recovering From an MS Relapse
Severe MS flares are usually treated with several days of high-dose, intravenous steroids, which can be administered at a medical facility or self-administered at home.
Steroids reduce inflammation and speed recovery from a flare, although they don’t correct the damage to the nervous system.
For people who can’t tolerate or don’t respond to steroids, there are other treatment options.
Some people recover fully from a flare, while in others, symptoms experienced during the flare linger afterward, though they may gradually improve over time.
Various forms of rehabilitation can help restore physical and mental functioning that’s been affected by an MS flare.
Additional reporting by Becky Upham.