Three cholinesterase inhibitors are commonly used to treat cognitive symptoms in mild-to-moderate AD: rivastigmine (Exelon®; Novartis, Basel, Switzerland), donepezil (Aricept®; Pfizer, New York, NY, USA) and galantamine (Reminyl®/Razadyne®; Johnson & Johnson, New Brunswick, NJ, USA). This evidence concerns the gene BCHE and Alzheimer disease.