CDP-Choline, also called citicoline, is a compound the body uses to build brain-cell membranes and make a memory-related signaling chemical. Its most consistent signal is modest support for age-related memory and thinking, mainly in older adults; smaller signals touch attention and optic-nerve protection. Safety is strong, with mild digestive upset most common. Evidence is suggestive, not settled. (Full Review)

Protocol

Dose

250–500 mg/day

500 mg/day is the most-studied dose in healthy older adults

Timing

Morning

Preferred to avoid sleep disruption; second dose by early afternoon

Frequency

Once daily

Single morning or split morning/afternoon dosing both used

Time to effect

Memory

4–12 weeks

Memory and cognitive-aging benefits build over daily use

Attention

Hours–days

Acute attention effects noticed by some users

Optic nerve

4–12 months

Visual-field measures in glaucoma studies

Benefits

Medium: Support for age-related memory decline; cognitive support in mild cognitive impairment and vascular cognitive decline

Low: Attention and psychomotor speed in healthy adults; retinal and optic-nerve neuroprotection; mood and motivation

Speculative: Long-term dementia prevention; neurorecovery and addiction-related cognition

Contraindications

Pregnancy & breastfeeding

Key Interactions

Levodopa/carbidopa

Cholinesterase inhibitors (donepezil, rivastigmine, galantamine)

Other choline donors, cholinergic nootropics (alpha-GPC, huperzine A)

Anticholinergics (diphenhydramine)

Blood-pressure-lowering supplements

Bipolar disorder

Risk & Side Effects

High: Gastrointestinal discomfort

Medium: Headache; sleep disturbance and restlessness

Low: Transient hypotension; anxiety and cholinergic overstimulation

Speculative: Trimethylamine N-oxide elevation; uridine-related effects

Monitoring

Marker	Target	Why
Homocysteine	5–7 µmol/L	Reflects methylation status tied to choline metabolism
Trimethylamine N-oxide (TMAO)	< 6.2 µmol/L	Screens the theoretical cardiovascular concern from the choline load
Blood pressure	< 120/80 mmHg	Detects the uncommon mild hypotensive effect
Vitamin B12 and folate	B12 500–900 pg/mL; folate upper-normal	Supports the methylation pathway that interacts with choline
Cognitive baseline (self-test or MMSE)	Individual baseline	Provides an objective anchor for judging benefit

Cadence: Reassess at 8–12 weeks after starting, then every 6–12 months if use continues

Qualitative Assessment

Everyday memory (recall of names, tasks, and recent events)
Focus and sustained attention during demanding work
Mental energy and clarity through the day
Mood and motivation
Sleep quality (watching for any disruption from dosing timing)

CDP-Choline for Health & Longevity

Protocol

Benefits

Risk & Side Effects

Monitoring

Qualitative Assessment