CDP-Choline (Citicoline)
Choline donor + cytidine source. Raises both acetylcholine (via choline) and dopamine/norepinephrine tone (via cytidine → uridine → neuronal membrane phospholipid synthesis). Gentler cognitive profile than alpha-GPC with additional dopamine-adjacent benefit.
Cytidine 5'-diphosphocholine. Metabolized in the gut to choline + cytidine; cytidine converts to uridine in circulation, which is a precursor for brain phosphatidylcholine synthesis. This dual precursor mechanism (choline for ACh + uridine for membrane repair) makes CDP-choline uniquely positioned as both a racetam cofactor and a standalone neuroprotective supplement. FDA-approved as a prescription drug in some countries (Recognan, Somazina). RCT evidence at 250-1000 mg/day in cognitive decline, traumatic brain injury, and stroke recovery — not in healthy young adults.
More stimulating than alpha-GPC for some users — avoid late dosing. Insomnia reported at 500 mg+ taken after noon. Headache at high doses possible (same as any choline source). Alpha-GPC vs CDP-choline: alpha-GPC has higher choline content per gram + more BBB penetration; CDP-choline has the uridine/dopaminergic component. Choose based on whether you want pure cholinergic vs broader neurochemistry.
External links to PubMed searches, ClinicalTrials.gov, and FDA materials. We do not host papers — we point at canonical sources.
DSHEA dietary supplement in US. Prescription drug in Japan, EU, and parts of LATAM (Recognan, Somazina). OTC supplement in US.
Distilled themes from named communities — Reddit threads, forums, creator commentary. Not direct quotes; not clinical evidence. Useful for calibrating expectations against what real self-experimenters report.
Cohort splits: users who want pure racetam support prefer alpha-GPC (higher choline content); users who want mood + focus lift prefer CDP-choline (uridine component). The 'stimulating' effect of CDP-choline is consistently reported — morning-only dosing is community wisdom. Both work for headache prevention with piracetam.