Pharmacology Autonomic nervous system 946c21b4 All are cholinergic drugs except A Memantine B Tacrine C Rivastigmine D Donepezil High-Yield Explanation Memantine acts on NMDA receptors .remaining all the drugs are indirectly acting cholinergicn drugs used in the treatment of alzhimers disease. Ref: KDT 6th ed pg 472,473