Relapse Management

Relapses, 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 and sometimes secondary-progressive forms of MS. Relapses also occur with progressive-relapsing MS, although as mentioned earlier, some experts are reclassifying this form of MS into one of the other more common forms. Relapses do not occur with primary-progressive MS, although people with PPMS 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.

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. 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 on relapse management, please visit MSAA’s MS Relapse Resource Center, found at Please also refer to MSAA’s MS Relapse Toolkit, with helpful tools for understanding MS relapses, learning about treatments, and preparing for these unexpected flare-ups in disease activity. Please visit to view or order a copy of this booklet.

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