MS relapses | Multiple Sclerosis News Today | illustration of damaged myelin

MS Relapses

Last updated Aug. 23, 2022, by Marisa Wexler, MS

Fact-checked by Ines Martins, PhD

An MS relapse refers to a worsening of symptoms without fever or infection

FAQs about MS relapses

“MS relapse” and “MS flare-up” are synonyms that can be used interchangeably. Both terms refer to a sudden worsening of multiple sclerosis (MS) symptoms in the absence of fever or infection. Other terms such as attack, clinical episode, and exacerbation also may be used in reference to an MS relapse.

The biological underpinnings of relapses in multiple sclerosis are incompletely understood, but broadly, relapses are driven by new or worsening inflammation damaging nerves in the brain and spinal cord. This can interfere with nerve signals and ultimately lead to the appearance of new symptoms or the worsening of older ones.

Some multiple sclerosis (MS) relapses are mild enough that they do not require treatment, whereas others may be severe enough to cause significant impairment. However, it’s generally recommended patients who think they are experiencing a relapse contact their healthcare team to determine the next steps in their management.

Multiple sclerosis (MS) exacerbations can cause any of the wide range of symptoms that may occur in MS; the specific symptoms depend on which parts of the nervous system are being actively damaged, and will vary from patient to patient and even from relapse to relapse for individuals. Some of the most common relapse symptoms include fatigue, pain or other unusual sensations, weakness, spasticity, difficulty with coordination or cognition, bladder problems, and vision difficulties.

Some multiple sclerosis patients are particularly sensitive to changes in body temperature and may experience a temporary worsening of multiple sclerosis symptoms called a pseudo-exacerbation. This worsening of symptoms may feel similar to an MS relapse, but it is not a true flare-up because these symptoms are not caused by active inflammation, and will resolve once body temperature returns to normal.

Multiple Sclerosis News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.

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