Reversible inhibitors, competitive or non-competitive (such as the current AD drugs donepezil and galantamine) and pseudo-irreversible inhibitor rivastigmine, a unique dual inhibitor of AChE and BuChE [8], have therapeutic applications, while toxic effects are normally associated with irreversible AChE inhibitors such as organophosphate pesticides and nerve warfare agents. Here, ACHE is linked to Alzheimer disease.