Multiple Sclerosis Relapses

MS Overview: RelapsesRelapses, also referred to as exacerbations, attacks, flare-ups, episodes, or bouts, are initially experienced by most people diagnosed with multiple sclerosis (MS). Relapses occur with relapsing-remitting, progressive-relapsing, and sometimes secondary-progressive forms of MS. Relapses do not occur with primary-progressive MS, although patients may experience day-to-day fluctuations in how they feel.

During a relapse, inflammation is occurring along the nerves and the myelin, causing patients to have a temporary worsening or recurrence of existing symptoms and/or the appearance of new symptoms. This can range from a few days in duration to a few months, followed by a complete or partial recovery (remission). Acute physical symptoms and neurological signs must be present for at least 24 to 48 hours, without any signs of infection or fever, before the treating physician may consider this type of flare-up to be a true relapse.

A pseudoexacerbation is a temporary worsening of symptoms without actual myelin inflammation or damage, brought on by other influences. Examples include other illnesses or infection, exercise, a warm environment, depression, exhaustion, and stress. When symptoms flare, checking for a fever is important, since even a minor infection and slight increase in temperature can cause symptoms to appear.

Photo of patient and doctor taking notesUrinary tract infection (UTI) is the most common type of infection to cause a pseudoexacerbation. Additionally, people with “heat-sensitive” MS will experience a temporary increase in symptoms when their body temperature rises, often after exercise. Many heat-sensitive individuals may opt to avoid hot tubs, saunas, or other situations that can raise the body’s temperature.

Relapses are usually treated with a high-dose course of powerful corticosteroids (a type of steroid) over a period of three to five days. These are given by intravenous (IV) infusion, administering the drug directly into the bloodstream for a quicker response. Administration may be performed at a hospital, infusion center, or sometimes at home. Some doctors prescribe oral steroids after the high-dose treatment, to ease the patient off of the medication. These are usually tapered over one to two weeks.

Another FDA-approved option is Acthar® Gel, which contains a highly purified form of the hormone adrenocorticotropin (ACTH). It is given once daily for two to three weeks and is injected either into the muscle or under the skin.

For more information, including details on the effectiveness and side effects of the different treatments for relapses, please visit MSAA’s online MS Relapse Resource Center. Individuals may also view or order MSAA’s brochure, Understanding and Treating MS Relapses, as well as MSAA’s MS Relapse Toolkit.


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