MEMANTINE
Low-affinity uncompetitive NMDA receptor antagonist approved for moderate-to-severe Alzheimer's disease; explored in OCD, autism, and vascular dementia.
Memantine is approved for moderate-to-severe Alzheimer's disease, where 20mg/day significantly slows cognitive and functional deterioration over 28 weeks in randomized controlled trials. Evidence for mild-to-moderate AD is less established. In vascular dementia, cognitive improvements were observed but not translated into clinically detectable functional changes. Off-label augmentation in OCD showed large effect sizes in meta-analysis but all trials originated from one region with methodological limitations. Preclinical autism research is promising but clinical results remain conflicting. Memantine provides symptomatic relief only, not disease modification.