ADMET 2 will examine in a masked, randomized trial the efficacy of methylphenidate for the treatment of clinically significant apathy in participants with Alzheimer's dementia. Efficacy will be assessed as the change in Neuropsychiatric Inventory Apathy subscale (NPI apathy) from baseline to 6 months and score on the Alzheimer's Disease Cooperative Study - Clinical Global Impression of Change (CGIC) scale at 6 months.