Memantine for cognitive impairment in multiple sclerosis: a randomized placebo-controlled trial.

Background: Memantine, an NMDA antagonist, is effective for moderate to severe Alzheimer's disease.

Objective: Determine whether memantine improves cognitive performance (CP) among subjects with multiple sclerosis (MS) and cognitive impairment (CI).

Methods: This double-blind, randomized, placebo-controlled trial (Clinicaltrials.