ACHE and Alzheimer disease: In fact, among the six drugs approved in the US to treat AD, four (tacrine, donepezil, rivastigmine and galantamine) are AChE inhibitors [27,28,29], memantine is a N-methyl-D-aspartic acid (NMDA) receptor (NMDAR) antagonist [30] and aduhelm (aducanumab) is a monoclonal antibody (amyloid targeting drug) that has been recently approved (in June 2021) [31].