In a trial testing the use of memantine (the active ingredient contained in Namenda XR) in MS patients with cognitive impairment, nine out of nineteen patients reported a worsening of their neurologic symptoms that deteriorated their quality of life. After stopping the
medication, the patients reverted to their baseline disability within a few days."
http://mymsaa.org/PDFs/MSAA.Motivator.Winter.Spring.2013.pdf
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