A more detailed investigation of the data regarding antidementia drugs in early- or late-onset AD showed that prescriptions for cholinesterase inhibitors (i.e. donepezil, rivastigmine or galantamine) had been filled in 56.9% of these cases; at least one cholinesterase inhibitor together with memantine was found in 15.1% of the population. This evidence concerns the gene BCHE and Alzheimer disease.