Memantine in dementia: a review of the current evidence.

INTRODUCTION: As the world's population ages, the incidence of Alzheimer's disease (AD) is projected to double every 20 years. Understanding the pathogenesis of AD and developing effective treatments is a public health imperative. Memantine is a low- to moderate-affinity, non-competitive NMDA receptor antagonist that is currently approved for the treatment of moderate to severe AD. AREAS COVERED: We discuss the current evidence, emphasizing more recent studies examining the effects of memantine in AD. We also look at the gaps in the current knowledge; the studies that will be required to fill these gaps are also discussed. The present paper reviews: the pharmacology of memantine; evidence for its use in moderate to severe AD, as well as in mild to moderate AD; adverse events related to memantine use; its effects specifically on behaviours including aggression and agitation; the pharmacoeconomics of memantine; and the use of memantine in other dementias. Memantine has shown modest benefits in cognition, function, global and behavioural measures, and has shown little potential for drug-drug interactions. EXPERT OPINION: For the treatment of moderate to severe AD, memantine should be offered as a therapeutic option, either on its own, or in combination with a cholinesterase inhibitor.