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A to Z of MS

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A to Z of MS Relapse

In multiple sclerosis, a relapse (also referred to as an attack, a flare up, an episode or exacerbation) is a sudden episode of symptoms or disability. It lasts at least 24 hours but more commonly for a number weeks. To be considered a new relapse, it must occur at least 30 days after the start of a previous episode and not be caused by infection or other cause.

A relapse is caused by inflammation of the myelin covering the nerve fibres. This delays or blocks the passage of messages along the nerve fibre which results in physical symptoms. The symptoms experienced depend on the area of the brain or spinal cord affected. Some relapses are relatively mild while others may cause more serious problems.

Symptoms similar to those of a relapse can occur when there is an infection, often a urine or respiratory infection. It is important to rule out infection before thinking that new symptoms are definitely due to a relapse.

MS relapses are often treated with steroids. Studies have shown that steroids are effective in speeding up recovery from relapse but make no difference either to the degree of recovery or to the long-term progression of the condition.

Reference

Burton JM, et al.
Oral versus intravenous steroids for treatment of relapses in multiple sclerosis.
Cochrane Database of Systematic Reviews 2009;(3):CD006921.
abstract

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