Citicoline

Evidence Level
Moderate
5 Clinical Trials
8 Documented Benefits
3/5 Evidence Score

Citicoline (CDP-choline) is a naturally-occurring intermediate in phosphatidylcholine biosynthesis, marketed primarily as the branded form Cognizin® (Kyowa Hakko Bio). Originally developed as a stroke pharmaceutical (Somazina®, prescribed in Europe and Japan), citicoline was later repositioned as an over-the-counter cognitive supplement. The best-supported use is episodic memory in older adults with age-associated memory impairment, and that rests on a single 12-week trial in 100 people funded by the maker of the Cognizin brand. The eye and attention claims are weaker: the only eye source cited here is a review article rather than a trial, and the attention study was done in 75 healthy adolescent boys, not in people with ADHD. Major caveat: the landmark ICTUS trial in 2,298 stroke patients was negative (odds ratio 1.03, 95% CI 0.86 to 1.25, p=0.364), and it used intravenous hospital dosing for the first 3 days, so it says nothing about oral supplements taken by healthy people.

Studied Dose 250–500 mg/day (as Cognizin®); cognitive: 500 mg/day; the large stroke trial used intravenous hospital dosing for the first 3 days and is not a guide for supplement use; well absorbed orally
Active Compound Citicoline (CDP-Choline) — Cognizin® branded form

Benefits

Memory in age-associated memory impairment

In one 12-week trial of 100 adults aged 50 to 85 who already had age-associated memory impairment, 500 mg/day of the Cognizin brand improved episodic memory (p=0.0025) and a composite memory score (p=0.0052) compared with placebo. Those were secondary outcomes, and the trial was funded by Kyowa Hakko Bio, the company that makes Cognizin. No independent replication is cited on this page, so the effect is promising rather than established. Best-fit population: older adults noticing subtle memory decline, not clinical dementia. Reasonable consideration for healthy older adults concerned about cognitive aging; not validated as a treatment for established dementia.

Glaucoma: review article only, not trial evidence

The only eye-related source cited on this page is a 2015 review article, not a clinical trial. That review describes small, preliminary studies in people with glaucoma in which citicoline appeared to slow loss of vision, and the review itself describes the evidence as preliminary rather than definitive. Glaucoma is a serious eye disease that can cause blindness and it needs care from an eye doctor. Citicoline is not a treatment for it, and nothing here should replace prescribed drops, laser treatment or surgery.

Acute ischemic stroke — popular claim, not validated

Earlier pooled analyses suggested citicoline reduces death and disability after stroke, leading to its approval in several countries. But the definitive 2,298-patient ICTUS trial found citicoline not efficacious in moderate-to-severe acute stroke. In that trial citicoline was given intravenously in hospital for the first 3 days, and the trial was funded by the drug's maker, Ferrer Grupo. Honest framing: a large, well-powered trial found no benefit (odds ratio 1.03, p=0.364), and because the dosing was intravenous and in a medical emergency, it tells you nothing about an oral supplement. Stroke needs emergency medical care.

Vascular cognitive impairment — modest evidence

None of the studies cited on this page tested citicoline in vascular cognitive impairment or in dementia, so this claim is not supported by the page's own references. The 1,000 mg/day dose quoted for this use is also about double the amount used in the memory trial cited here. Memory changes caused by vascular disease need a doctor's assessment. Managing blood pressure and other risk factors is what has actually been shown to matter.

Traumatic brain injury — popular claim, not validated

Earlier observational data and smaller trials suggested citicoline aids TBI recovery. But the definitive 1,213-patient COBRIT trial in moderate-to-severe TBI found NO significant improvement in functional or cognitive outcomes vs placebo. Smaller trials in mild brain injury are not among the references cited here and are not conclusive. Honest framing: established TBI benefit is unproven at scale despite the popular nootropic-community framing of citicoline as 'recovery support.'

Attention: studied in healthy teenage boys, not in ADHD

The attention study cited on this page was done in 75 healthy adolescent boys, not in people diagnosed with ADHD. Over 28 days, 250 or 500 mg/day improved attention and motor speed and reduced impulsivity compared with placebo. It was small, short and manufacturer-supported, and no study cited here tested citicoline in people with ADHD. ADHD is a medical diagnosis that needs professional care, and citicoline has not been shown to treat it. Never change or stop prescribed ADHD medication without talking to your prescriber.

Cocaine dependence in bipolar disorder

A trial in adults being treated for both bipolar disorder and cocaine dependence reported less cocaine use with citicoline 2,000 mg/day over 12 weeks, but that study is not among the references listed on this page, so its details are not verified here. That dose is four times the usual supplement amount and was used in a supervised clinical trial. Specialized clinical application; not validated for general substance use disorder treatment. Citicoline is not a treatment for addiction or for bipolar disorder, and both need professional medical care.

Cognitive enhancement in healthy young adults — limited

The one study cited here in a young population was in 75 healthy adolescent boys taking 250 or 500 mg/day for 28 days, and it was manufacturer-supported. It reported better attention and motor speed than placebo. Studies in this area are short and mostly industry-funded. Effects are subtle and not reliably distinguishable from placebo at the individual level. If you're a healthy young adult, citicoline may not produce noticeable effects; the population most likely to benefit is older adults with age-related decline.

Mechanism of action

1

Precursor to Phosphatidylcholine Synthesis

Citicoline provides cytidine and choline, which are used to synthesize phosphatidylcholine, a key component of neuronal membranes, supporting their repair and integrity.

2

Acetylcholine Production

Citicoline serves as a choline source, increasing acetylcholine synthesis, a neurotransmitter essential for memory, learning, and cognitive function.

3

Neuroprotection: a Laboratory Mechanism Not Confirmed in Human Trials

In laboratory and animal studies citicoline reduces oxidative stress and cell death. That is a proposed mechanism only: the two largest human trials, in acute stroke (2,298 patients) and in traumatic brain injury (1,213 patients), found no benefit over placebo.

4

Enhances Neuroplasticity

In animal and cell studies citicoline supports phospholipid synthesis and raises brain-derived neurotrophic factor (BDNF). These effects have not been demonstrated in people in the studies cited here.

5

Modulates Neurotransmitter Systems

Laboratory work suggests citicoline influences dopamine and serotonin pathways. None of the studies cited on this page measured mood or cravings, so this is a theory, not a demonstrated effect.

6

Possible Role in Mitochondrial Energy Production

In laboratory models citicoline has been linked to higher ATP production and better mitochondrial function. Whether this translates into any noticeable effect on brain energy in people has not been shown in the studies cited here.

7

Effects on Inflammation in Lab Studies

In cell and animal studies citicoline lowers inflammatory signalling molecules and stabilizes cell membranes. No study cited on this page measured inflammation in people.

8

Supports Retinal Ganglion Cell Function

Researchers have proposed that by supplying phospholipids and reducing oxidative damage, citicoline may support retinal cells. This idea comes from a review of small preliminary studies; citicoline is not a treatment for glaucoma or any other eye disease.

Clinical trials

1
Acute Stroke: large trial that found no benefit

Randomized placebo-controlled trial in 2,298 patients with moderate to severe acute ischemic stroke. Citicoline was given as 1,000 mg INTRAVENOUSLY every 12 hours for the first 3 days and only then by mouth, so this is a hospital drug protocol, not a supplement regimen.

2,298 patients with moderate-to-severe acute ischemic stroke across Germany

Randomized placebo-controlled trial in 2,298 patients with moderate-to-severe acute ischemic stroke, funded by Ferrer Grupo, the company that makes the drug. Citicoline was given as 1,000 mg intravenously every 12 hours for 3 days, then 500 mg by mouth twice daily, starting within 24 hours of the stroke. The primary endpoint was not met: global recovery odds ratio 1.03 (95% CI 0.86 to 1.25, p=0.364). The authors concluded that citicoline is not efficacious in the treatment of moderate-to-severe acute ischaemic stroke. This is a large negative trial of a hospital drug protocol, and it is not evidence for an oral supplement.

2
Memory in Healthy Older Adults

Clinical trial in 100 healthy adults aged 50-85 with age-associated memory impairment.

100 healthy adults aged 50-85 with age-associated memory impairment

Clinical trial in 100 healthy adults aged 50-85 with age-associated memory impairment. Cognizin® 500 mg/day vs placebo × 12 weeks. Improvements were seen on secondary outcomes: episodic memory (p=0.0025) and a composite memory score (p=0.0052). The primary outcome is not clearly reported, so the headline memory result rests on secondary measures. Ninety-nine of the 100 participants completed the study. It was funded by Kyowa Hakko Bio, which makes the Cognizin brand used, and no independent replication is cited on this page.

3
Citicoline for Glaucoma — 3-Year Clinical Trial

A 2015 review article, not a clinical trial. It is the only eye-related item cited on this page.

Clinical population described in trial publication.

The eye-health evidence cited on this page is a 2015 review article, not a clinical trial. It summarizes small, preliminary studies in people with open-angle glaucoma in which citicoline appeared to slow loss of visual field, and it describes that evidence as preliminary. Glaucoma is a serious eye disease treated by an eye doctor with pressure-lowering drops, laser or surgery, and citicoline is not a substitute for that care.

4
Zafonte COBRIT 2012 — Traumatic Brain Injury

Citicoline Brain Injury Treatment Trial: 1,213 patients with moderate-severe TBI randomized to citicoline 2,000 mg/day vs placebo × 90 days.

1,213 patients with moderate-severe TBI

Citicoline Brain Injury Treatment Trial: 1,213 patients with moderate-severe TBI randomized to citicoline 2,000 mg/day vs placebo × 90 days. The trial was stopped early for futility, with no significant difference from placebo in functional or cognitive outcomes. No major safety problems were reported. This study is not among the references listed on this page, but along with the ICTUS stroke trial it means the two largest trials of citicoline in acute brain injury and stroke both failed to show benefit.

5
Cocaine Dependence in Bipolar Disorder

Clinical trial in 130 outpatients with bipolar I/II and cocaine dependence.

Clinical population described in trial publication.

Clinical trial in 130 outpatients with bipolar I/II and cocaine dependence. Citicoline 2,000 mg/day versus placebo for 12 weeks, which is four times the usual supplement dose, reportedly reduced cocaine use. This study is not among the references listed on this page, so its details are not verified here. It was done in people receiving specialist psychiatric care, and citicoline is not a treatment for addiction or bipolar disorder.

Side effects and drug interactions

Common Potential side effects

Mild GI discomfort (nausea, diarrhea, stomach upset) — most common, dose-related.
Headache — possibly from increased acetylcholine activity.
Insomnia or vivid dreams — citicoline has mild stimulating effects; avoid evening dosing.
Mild hypotension occasionally reported.
Heart palpitations at high doses (>2 g/day) in sensitive individuals.
Well tolerated at 500 mg/day in a 12-week trial in older adults; doses of 1,000 to 2,000 mg have mainly been used in hospital and clinical trial settings under medical supervision, so long-term safety of high doses in everyday use is not well established.
Rare allergic reactions (rash, itching).

Important Drug interactions

Levodopa: citicoline has been studied alongside levodopa in Parkinson's disease; if you take levodopa, ask your doctor before adding citicoline
Cholinesterase inhibitors (donepezil, rivastigmine) — additive cholinergic activity; monitor for excess cholinergic symptoms (nausea, bradycardia, excess secretions)
Anticholinergic medications — citicoline may partially offset anticholinergic drug effects
No serious drug interactions established at standard supplemental doses (250–500 mg/day)

Frequently asked questions about Citicoline

How much citicoline (CDP-choline) should I take?

Common doses are 250 to 500 mg per day, sometimes split into two. The 12-week memory trial in older adults used 500 mg per day of the branded Cognizin form, and the 28-day study in healthy adolescent boys used 250 or 500 mg per day.

What is citicoline used for?

Citicoline (CDP-choline) supplies choline and cytidine to the brain, supporting acetylcholine production and cell-membrane health. It has been studied for attention and memory. The strongest cited evidence is a 12-week trial in 100 older adults with age-related memory complaints, funded by the maker of the Cognizin brand.

When should I take citicoline?

It is typically taken in the morning or earlier in the day for focus, with or without food. Splitting it into a morning and midday dose is also common. It is not sedating.

Does citicoline have side effects?

Citicoline is generally well tolerated; occasional mild effects include headache, stomach upset, or trouble sleeping if taken late. Most of the safety information comes from short studies lasting a few weeks to 3 months, so effects of taking it for years are not well studied.

What is Citicoline?

Citicoline (CDP-choline) is a naturally-occurring intermediate in phosphatidylcholine biosynthesis, marketed primarily as the branded form Cognizin® (Kyowa Hakko Bio).

What is the recommended dosage of Citicoline?

The clinically studied dose is 250–500 mg/day (as Cognizin®); cognitive: 500 mg/day; the large stroke trial used intravenous hospital dosing for the first 3 days and is not a guide for supplement use; well absorbed orally Always follow the product label and check with a healthcare provider for personal advice.

Is Citicoline safe, and does it have side effects?

For most healthy adults, Citicoline is well tolerated at studied doses. Reported effects can include: Mild GI discomfort (nausea, diarrhea, stomach upset) — most common, dose-related. Headache — possibly from increased acetylcholine activity. It may also interact with some medications. Citicoline is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does Citicoline interact with any medications?

Possible interactions include: Levodopa: citicoline has been studied alongside levodopa in Parkinson's disease; if you take levodopa, ask your doctor before adding citicoline Cholinesterase inhibitors (donepezil, rivastigmine) — additive cholinergic activity; monitor for excess cholinergic symptoms (nausea, br… If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for Citicoline?

NutraSmarts rates the evidence for Citicoline as Moderate (3 out of 5). It is backed by 5 clinical trials and 4 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(4 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. McGlade E, Agoston AM, DiMuzio J, Kizaki M, Nakazaki E, Kamiya T, Yurgelun-Todd D. The Effect of Citicoline Supplementation on Motor Speed and Attention in Adolescent Males. J Atten Disord. 2019;23(2):121-134. doi: 10.1177/1087054715593633.PubMedUsed to support: Backs the attention/cognition claim. In 75 healthy adolescent males, 28 days of citicoline (250 or 500 mg) improved attention and psychomotor/motor speed and reduced impulsivity versus placebo. Small, short, manufacturer-supported trial in healthy teenage boys, not in people with ADHD, so it should not be used to support ADHD claims or claims about adults.
  2. Nakazaki E, Mah E, Sanoshy K, Citrolo D, Watanabe F. Citicoline and Memory Function in Healthy Older Adults: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial. J Nutr. 2021;151(8):2153-2160. doi: 10.1093/jn/nxab119.PubMedUsed to support: Backs the memory claim. In 100 healthy older adults with age-associated memory impairment, 12 weeks of citicoline 500 mg/day improved composite and episodic memory measures versus placebo. The gains were on secondary outcomes, the trial was funded by Kyowa Hakko Bio (which makes the Cognizin form used), and the participants already had memory complaints.
  3. Davalos A, Alvarez-Sabin J, Castillo J, Diez-Tejedor E, Ferro J, Martinez-Vila E, Serena J, Segura T, Cruz VT, Masjuan J, et al. Citicoline in the treatment of acute ischaemic stroke: an international, randomised, multicentre, placebo-controlled study (ICTUS trial). Lancet. 2012;380(9839):349-57. doi: 10.1016/S0140-6736(12)60813-7.PubMedUsed to support: Included for honesty: this large landmark trial was negative. In 2,298 patients with moderate-to-severe acute ischemic stroke, citicoline did not improve recovery versus placebo (OR 1.03, 95% CI 0.86 to 1.25; p=0.364). It was given intravenously for the first 3 days and the trial was funded by Ferrer Grupo, which makes the drug. Tempers any claim that citicoline is a proven treatment for stroke/serious neurological injury, even though small earlier studies were encouraging.
  4. Roberti G, Tanga L, Michelessi M, Quaranta L, Parisi V, Manni G, Oddone F. Cytidine 5'-Diphosphocholine (Citicoline) in Glaucoma: Rationale of Its Use, Current Evidence and Future Perspectives. Int J Mol Sci. 2015;16(12):28401-17. doi: 10.3390/ijms161226099.PubMedUsed to support: This is a review article, not a clinical trial, and it is the only eye-related source cited on this page. It summarizes early evidence that citicoline (oral or eye-drop) might have a protective role in glaucoma, with some studies showing improved retinal function and slowed visual-field deterioration. Framed cautiously: evidence is preliminary and from small studies, not large definitive RCTs.