All are cholinergic agents EXCEPT:
Ref: KD Tripathi pharmacology 7th edition (page.no:489) All these drugs are used in Alzheimer's disease. But only A,B,C increase cholinergic activity in Alzheimer's. Memantine is a Glutamate Antagonist.it is an NMDA blocker Examples of direct-acting cholinergic agents include choline esters (acetylcholine, methacholine, carbachol, bethanechol, tacrine) and alkaloids (muscarine, pilocarpine, cevimeline)
Gallantamine
Donepezil
Tacrine
Memantine
Autonomic nervous system