Brain, mood & sleep
Cholinesterase inhibitor
Donepezil
Also known as: Aricept
Best time
Bedtime (or morning if dreams disturb sleep)
- 21:00–23:00
Bedtime dosing lets people sleep through nausea; switch to mornings if it causes vivid dreams.
Moderate evidence
Supported by studies and drug pharmacology, but guidance varies between sources.
Why this time works
Peak blood levels occur a few hours after dosing, when side effects like nausea are most likely. Night dosing helps people sleep through them, but cholinergic effects can cause vivid dreams or insomnia, in which case morning dosing is used.
Body rhythm involved
Acetylcholine levels are high in REM sleep and active wakefulness.