These patients will be grouped according to the medications prescribed by their attending physician at baseline, 3rd month, and 6th month of follow up:~Alzheimer's Disease patients given AChE inhibitor monotherapy~Alzheimer's Disease patients given combination therapy of AChE inhibitor and NMDA receptor antagonist~They will be observed for treatment response for up to 6 months.
This study will explore the different factors associated with drug response to acetylcholinesterase (AChE) inhibitor (donepezil) and NMDA receptor antagonist (memantine) in patients with Alzheimer's Disease.