Oxiracetam

Pharmacology & Research

Oxiracetam is a synthetic, water-soluble racetam — a structural derivative of piracetam built on the same 2-pyrrolidinone ring — developed in the 1970s–80s (as ISF-2522 / CGP 21690E) and studied almost entirely as a treatment for impaired cognition rather than enhancement in healthy people. That distinction is the key to reading its evidence: the compound has a real, if modest, signal in acquired cognitive injury — a large modern phase 3 trial found it improved cognition after traumatic brain injury ^{1Reference 1Efficacy et al. · 2025RCTSignal Transduction and Targeted TherapyView study →} — but the most rigorous prevention trial in post-stroke patients was flatly negative — a result whose authors note supports South Korea’s regulatory decision to suspend its use ^{2Reference 2Oxiracetam et al. · 2026RCTOxiracetam and physical activity in preventing cognitive decline after stroke: a multicenter, randomized controlled trial (2026) — [randomised controlled trial]. European Stroke Journal. https://pubmed.ncbi.nlm.nih.gov/41614470/View study →}. The popular use as a general “study aid” in healthy adults rests on almost no direct evidence. Pharmacologically it is unusual for a nootropic in being barely metabolised — the great majority is excreted unchanged by the kidneys — so renal function, not liver metabolism, governs its clearance ^{3,4Reference 3Absorption et al. · 1992AnimalAbsorption and disposition of 14C-labelled oxiracetam in rat, dog and man (1992) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/1499599/View study →Reference 4Oxiracetam pharmacokinetics following si et al. · 1987Oxiracetam pharmacokinetics following single and multiple dose administration in the elderly (1987) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/3691580/View study →}.

1. Traumatic brain injury recovery

The strongest single piece of evidence. A 2025 multicentre, double-blind, randomised phase 3 trial in China enrolled 590 patients with mild-to-moderate TBI (Glasgow Coma Scale 10–15) and randomised them 2:2:1 to L-oxiracetam 4 g/day, racemic oxiracetam 6 g/day, or placebo for 90 days ^{1Reference 1Efficacy et al. · 2025RCTSignal Transduction and Targeted TherapyView study →}. On the primary cognitive endpoint (LOTCA), both active arms beat placebo; L-oxiracetam showed a mean advantage of ~9 points over placebo (Cohen’s d = 0.48, a moderate effect) and was modestly better than the racemate ^{1Reference 1Efficacy et al. · 2025RCTSignal Transduction and Targeted TherapyView study →}. Serious adverse events did not differ between groups ^{1Reference 1Efficacy et al. · 2025RCTSignal Transduction and Targeted TherapyView study →}. Note the caveats: doses are far higher (4–6 g/day) than the 750–1,600 mg/day sold as a supplement, the trial was single-country, and there was meaningful loss to follow-up.

Gap: A single (albeit large) positive trial at high dose in one country; not yet independently replicated, and the supplement dose is a fraction of what was tested.

2. Vascular cognitive impairment

The largest body of oxiracetam data is in vascular/multi-infarct cognitive impairment, but it is uneven. Older double-blind trials from the 1980s–90s reported benefits on scales such as the IPSC-E, Blessed Dementia Scale and MMSE in mixed degenerative/multi-infarct dementia ^{6,9Reference 6Oxiracetam in the treatment of primary d et al. · 1989RCTOxiracetam in the treatment of primary degenerative and multi-infarct dementia: a double-blind, placebo-controlled study (1989) — [randomised controlled trial]. Neuropsychobiology. https://pubmed.ncbi.nlm.nih.gov/2693996/View study →Reference 9Oxiracetam in dementia: a double-blind · 1992RCTOxiracetam in dementia: a double-blind, placebo-controlled study (1992) — [randomised controlled trial]. Acta Neurologica Scandinavica. https://pubmed.ncbi.nlm.nih.gov/1414239/View study →}. In modern practice (mainly China), it is often used adjunctively — a 120-patient trial found nicergoline plus oxiracetam improved MoCA more than nicergoline alone ^{5Reference 5Clinical efficacy et al. · 2020RCTClinical efficacy and safety of nicergoline combined with oxiracetam in the treatment of vascular cognitive impairment (2020) — [randomised controlled trial]. Pakistan Journal of Pharmaceutical Sciences. https://pubmed.ncbi.nlm.nih.gov/32173636/View study →}. A 2024 Bayesian network meta-analysis of 194 vascular-dementia RCTs placed oxiracetam among the drugs with a favourable safety profile, but not among the most effective ^{10Reference 10Pharmacological treatments for vascular et al. · 2024Meta-analysisPharmacological treatments for vascular dementia: a systematic review and Bayesian network meta-analysis (2024) — [systematic review / meta-analysis]. Frontiers in Pharmacology. https://pubmed.ncbi.nlm.nih.gov/39239652/View study →}. Critically, the best modern trial — a 500-patient Korean RCT testing whether oxiracetam could prevent post-stroke cognitive impairment — found no difference from placebo on MMSE or CDR-SB over 36 weeks ^{2Reference 2Oxiracetam et al. · 2026RCTOxiracetam and physical activity in preventing cognitive decline after stroke: a multicenter, randomized controlled trial (2026) — [randomised controlled trial]. European Stroke Journal. https://pubmed.ncbi.nlm.nih.gov/41614470/View study →}.

Gap: Treatment-of-established-impairment trials are old and mostly positive; the one rigorous modern prevention trial was null, so the benefit may be confined to already-impaired patients.

3. Dementia & degenerative decline

Results split sharply by dementia type and trial rigour. Several older placebo-controlled trials in mild-to-moderate primary degenerative or mixed dementia reported improvements on MMSE, attention and instrumental activities of daily living at 1,600 mg/day ^{7,9Reference 7Effects of acute doses of oxiracetam in · 1993RCTEffects of acute doses of oxiracetam in the scopolamine model of human amnesia (1993) — [randomised controlled trial]. Psychopharmacology. https://pubmed.ncbi.nlm.nih.gov/7870912/View study →Reference 9Oxiracetam in dementia: a double-blind · 1992RCTOxiracetam in dementia: a double-blind, placebo-controlled study (1992) — [randomised controlled trial]. Acta Neurologica Scandinavica. https://pubmed.ncbi.nlm.nih.gov/1414239/View study →}. But in the disease people most associate with dementia — Alzheimer’s — a carefully conducted double-blind trial found oxiracetam produced no improvement on any neuropsychological measure and concluded it was “ineffective in reducing cognitive impairment due to Alzheimer’s disease” ^{8Reference 8Treatment trial of oxiracetam in Alzheim · 1992Clinical trialTreatment trial of oxiracetam in Alzheimer’s disease (1992) — [clinical trial, negative]. Archives of Neurology. https://pubmed.ncbi.nlm.nih.gov/1444879/View study →}.

Gap: The positive signals are in heterogeneous, loosely defined “degenerative dementia” from decades-old trials; the cleaner Alzheimer’s trial was negative.

4. Healthy cognitive enhancement

This is what most supplement buyers actually want, and it is the weakest-evidenced use. There is no published RCT showing oxiracetam improves real-world cognition in healthy, non-impaired adults. The nearest human data is a “scopolamine model of amnesia” study in 12 healthy volunteers: an acute 1,600 mg dose partly reversed the memory impairment induced by scopolamine, and showed dose-related antagonism of that chemical deficit ^{7Reference 7Effects of acute doses of oxiracetam in · 1993RCTEffects of acute doses of oxiracetam in the scopolamine model of human amnesia (1993) — [randomised controlled trial]. Psychopharmacology. https://pubmed.ncbi.nlm.nih.gov/7870912/View study →}. That is a pharmacodynamic challenge model — evidence the drug engages memory pathways — not evidence it makes an unimpaired brain perform better.

Gap: Benefit in healthy users is inferred from a deficit-reversal model, not demonstrated; the everyday “focus and logical thinking” claim is essentially untested in trials.

Mechanisms

Target / pathway	Effect	Relevant to
Cholinergic signalling	Increases high-affinity choline uptake and acetylcholine turnover	Memory, learning; rationale for pairing with a choline source
Glutamatergic AMPA/NMDA receptors	Positive modulation; facilitates long-term potentiation	Memory consolidation, TBI/VCI recovery
Membrane phospholipid / PKC signalling	Modulation (preclinical)	Proposed neuroprotection
Cerebral energy metabolism	Enhanced glucose/ATP utilisation (older preclinical claims)	Age-related and vascular cognitive decline

Pharmacokinetics

Oxiracetam is absorbed rapidly after oral dosing, with peak plasma levels at roughly 1–2 hours ^{4,12Reference 4Oxiracetam pharmacokinetics following si et al. · 1987Oxiracetam pharmacokinetics following single and multiple dose administration in the elderly (1987) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/3691580/View study →Reference 12Pharmacokinetics of oxiracetam following et al. · 1984Pharmacokinetics of oxiracetam following intravenous and oral administration in healthy volunteers (1984) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/6519128/View study →}. Oral bioavailability in humans is intermediate — about 56% — sitting between poor absorption in rats (28–42%) and high absorption in dogs (81–90%) ^{3Reference 3Absorption et al. · 1992AnimalAbsorption and disposition of 14C-labelled oxiracetam in rat, dog and man (1992) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/1499599/View study →}. The defining feature is that it is not appreciably metabolised: more than 80–90% of a dose is recovered unchanged in the urine, so the kidneys, not the liver, clear it ^{3,4,12Reference 3Absorption et al. · 1992AnimalAbsorption and disposition of 14C-labelled oxiracetam in rat, dog and man (1992) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/1499599/View study →Reference 4Oxiracetam pharmacokinetics following si et al. · 1987Oxiracetam pharmacokinetics following single and multiple dose administration in the elderly (1987) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/3691580/View study →Reference 12Pharmacokinetics of oxiracetam following et al. · 1984Pharmacokinetics of oxiracetam following intravenous and oral administration in healthy volunteers (1984) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/6519128/View study →}. The terminal elimination half-life is short in people with normal kidneys — about 3–6 hours after an 800 mg dose — which is why it is dosed 2–3 times daily and shows little accumulation on twice-daily maintenance ^{4Reference 4Oxiracetam pharmacokinetics following si et al. · 1987Oxiracetam pharmacokinetics following single and multiple dose administration in the elderly (1987) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/3691580/View study →}. Two clinically important modifiers: renal impairment dramatically prolongs the half-life (from ~3–6 h up to 10–68 h as creatinine clearance falls), so the dose must be reduced in kidney disease ^{11Reference 11Pharmacokinetics of oxiracetam in patien · 1990Clinical trialPharmacokinetics of oxiracetam in patients with renal impairment after a 800 mg single oral dose (1990) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/2253654/View study →}; and the antiepileptics carbamazepine and valproate shorten its half-life, requiring more frequent dosing in patients taking them ^{13Reference 13Pilot study to determine the interaction · 1990Pilot study to determine the interaction of oxiracetam with antiepileptic drugs (1990) — [pharmacokinetics]. Clinical Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/2108837/View study →}. Oxiracetam has a chiral centre, and its S-(L-)enantiomer is the pharmacologically active form now being developed separately in China ^{1,14Reference 1Efficacy et al. · 2025RCTSignal Transduction and Targeted TherapyView study →Reference 14Safety et al. · 2024RCTSafety, tolerability, and pharmacokinetics of oral (S)-oxiracetam in Chinese healthy volunteers: a randomized, double-blind, controlled phase I study (2024) — [randomised controlled trial]. European Journal of Pharmaceutical Sciences. https://pubmed.ncbi.nlm.nih.gov/37898393/View study →}.

Clinical trials

Oxiracetam is off-patent and decades old, so there is little Western pharmaceutical trial activity — Western registries list essentially one recent study, while contemporary trials are registered on Chinese and Korean registries. The two largest modern trials (a positive phase 3 in TBI and a null prevention trial in post-stroke patients) were both conducted in East Asia.

Last checked: July 2026.

Intake & Dosage

Because oxiracetam is not a nutrient, there is no RDA, no AI, and no Tolerable Upper Intake Level — the concept of correcting a deficiency does not apply. The doses to reference are those studied in research, not a personal recommendation.

• Common supplement range: 750–1,600 mg/day, typically split into 2–3 doses 6–8 hours apart. The short (~3–6 h) half-life is the reason for split dosing ^{4Reference 4Oxiracetam pharmacokinetics following si et al. · 1987Oxiracetam pharmacokinetics following single and multiple dose administration in the elderly (1987) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/3691580/View study →}.
• Research doses run much higher: the modern TBI phase 3 trial used 6 g/day of racemic oxiracetam (4 g/day of the L-enantiomer), and vascular-impairment trials commonly used 1,600 mg/day ^{1,6Reference 1Efficacy et al. · 2025RCTSignal Transduction and Targeted TherapyView study →Reference 6Oxiracetam in the treatment of primary d et al. · 1989RCTOxiracetam in the treatment of primary degenerative and multi-infarct dementia: a double-blind, placebo-controlled study (1989) — [randomised controlled trial]. Neuropsychobiology. https://pubmed.ncbi.nlm.nih.gov/2693996/View study →}.
• Renal impairment: clearance is almost entirely renal, and half-life lengthens dramatically as kidney function falls — doses should be reduced in kidney disease ^{3,11Reference 3Absorption et al. · 1992AnimalAbsorption and disposition of 14C-labelled oxiracetam in rat, dog and man (1992) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/1499599/View study →Reference 11Pharmacokinetics of oxiracetam in patien · 1990Clinical trialPharmacokinetics of oxiracetam in patients with renal impairment after a 800 mg single oral dose (1990) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/2253654/View study →}.
• Enzyme-inducing antiepileptics (carbamazepine, valproate) shorten its half-life, so more frequent dosing may be needed in those patients ^{13Reference 13Pilot study to determine the interaction · 1990Pilot study to determine the interaction of oxiracetam with antiepileptic drugs (1990) — [pharmacokinetics]. Clinical Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/2108837/View study →}.
• With food / choline: many users pair it with a choline donor to offset racetam-associated headache; this is a practical convention, not a trial-validated protocol.

These are doses studied in research, not a personal recommendation.

Safety

Across the trial record oxiracetam has been generally well tolerated, with adverse events that were mild, dose-independent, and often no more frequent than placebo ^{1,6,14Reference 1Efficacy et al. · 2025RCTSignal Transduction and Targeted TherapyView study →Reference 6Oxiracetam in the treatment of primary d et al. · 1989RCTOxiracetam in the treatment of primary degenerative and multi-infarct dementia: a double-blind, placebo-controlled study (1989) — [randomised controlled trial]. Neuropsychobiology. https://pubmed.ncbi.nlm.nih.gov/2693996/View study →Reference 14Safety et al. · 2024RCTSafety, tolerability, and pharmacokinetics of oral (S)-oxiracetam in Chinese healthy volunteers: a randomized, double-blind, controlled phase I study (2024) — [randomised controlled trial]. European Journal of Pharmaceutical Sciences. https://pubmed.ncbi.nlm.nih.gov/37898393/View study →}. The most commonly reported issues are headache (the reason for the choline-pairing convention), mild gastrointestinal upset (loose stools were the main finding in canine toxicology), and — consistent with its mildly stimulating quality — occasional restlessness, agitation or insomnia if taken late in the day. Serious adverse events were not elevated versus placebo in the large modern TBI trial ^{1Reference 1Efficacy et al. · 2025RCTSignal Transduction and Targeted TherapyView study →}.

Two safety points deserve emphasis. First, oxiracetam is cleared almost entirely by the kidneys, so renal impairment both raises exposure and prolongs the half-life several-fold — a dose reduction is warranted ^{3,11Reference 3Absorption et al. · 1992AnimalAbsorption and disposition of 14C-labelled oxiracetam in rat, dog and man (1992) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/1499599/View study →Reference 11Pharmacokinetics of oxiracetam in patien · 1990Clinical trialPharmacokinetics of oxiracetam in patients with renal impairment after a 800 mg single oral dose (1990) — [pharmacokinetics]. European Journal of Drug Metabolism and Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/2253654/View study →}. Second, it has a documented pharmacokinetic interaction with the antiepileptics carbamazepine and valproate, which shorten its half-life; the interaction did not appear to change antiepileptic drug levels, and concurrent use was not judged contraindicated, but dosing frequency may need adjustment ^{13Reference 13Pilot study to determine the interaction · 1990Pilot study to determine the interaction of oxiracetam with antiepileptic drugs (1990) — [pharmacokinetics]. Clinical Pharmacokinetics. https://pubmed.ncbi.nlm.nih.gov/2108837/View study →}.

Regulatory status is a genuine caveat, not a formality: oxiracetam is not approved as a drug or dietary supplement in the United States, and its use is subject to a regulatory suspension in South Korea — a decision the authors of a 500-patient trial (which found no benefit for preventing post-stroke cognitive decline) say their findings support ^{2Reference 2Oxiracetam et al. · 2026RCTOxiracetam and physical activity in preventing cognitive decline after stroke: a multicenter, randomized controlled trial (2026) — [randomised controlled trial]. European Stroke Journal. https://pubmed.ncbi.nlm.nih.gov/41614470/View study →}.

Pregnancy & lactation

Verdict: avoid. There are no human pregnancy or lactation safety data for oxiracetam, and no basis to establish safety. In the absence of any studies, it should not be used during pregnancy or breastfeeding.

References