Abstract
Donepezil 10 mg/day has been a modestly successful therapeutic agent for the palliative treatment of Alzheimer disease dementia. In 2011, seeking greater efficacy and an extension of the Aricept brand, a 23-mg formulation of donepezil was introduced. A large-scale trial, organized by Eisai, the sponsor, failed to show superiority in their primary analyses of donepezil 23 mg/day in patients with moderate to severe Alzheimer disease dementia vs 10 mg, but the published report used post hoc analyses to claim "statistically significant benefits." There was greater than a 3 times higher rate of gastrointestinal side effects with 23 mg of donepezil compared to 10 mg. Thus, not only does donepezil 23 mg/day increase the likelihood of unacceptable gastrointestinal side effects, it provides no clinical benefits. Aricept 23 mg is about 10 times more costly per pill than donepezil 10 mg.