Aniracetam
Aniracetam is a fat-soluble pyrrolidinone ("racetam") nootropic developed by Roche (Ro 13-5057) and studied in the 1980s-1990s mainly in elderly patients with Alzheimer-type or vascular dementia. It is taken orally for claimed memory, attention and mood benefits. The most important safety realities are: (1) essentially no controlled human data exist in healthy adults using it as a cognitive enhancer, so benefit and safety in that population are unknown; (2) the clinical trials that do exist were small, in cognitively impaired elderly people, and gave conflicting results (one positive multicentre trial, one negative trial, one negative solvent-psychosyndrome trial); (3) at least one randomized trial reported drug-induced confusion leading to discontinuation. It is not an approved drug in most countries and is sold as an unregulated "research chemical"/supplement, meaning product identity, purity and dose are not guaranteed. Lead concerns are neuropsychiatric (confusion, agitation, anxiety, insomnia), unknown long-term safety, and impaired clearance of its metabolites in people with reduced kidney function or advanced age.
Mechanism of action
Pharmacokinetics
Parent aniracetam has a very short plasma elimination half-life of roughly 0.5 h (t1/2 ~0.47 h after a 400 mg oral dose in healthy young men) due to near-complete first-pass metabolism; the principal metabolites (anisic acid, p-methoxyhippuric acid, N-anisoyl-GABA) persist for hours and their half-life is prolonged 4- to 7-fold in elderly patients with cerebrovascular disease and reduced renal function.
Short; metabolite serum levels peak ~2 h after an oral dose and return toward baseline by ~6 h in elderly patients, consistent with the multiple-daily-dosing schedules used in trials.
Oral (fat-soluble; taken with food to improve absorption of an otherwise poorly bioavailable parent compound).
Extensive/near-complete hepatic first-pass metabolism of the parent to anisic acid (p-anisic acid), p-methoxyhippuric acid and N-anisoyl-GABA (4-p-anisamidobutyric acid, an active metabolite); metabolites are cleared renally. Clearance is markedly slowed with aging and renal impairment (elderly CVD patients had creatinine clearance ~20-30 mL/min with 4-7x longer metabolite half-lives). For monitoring/washout only, not for evading testing.
For monitoring and washout planning, not drug-test evasion.
Physiological & performance effects
- Studied as a cognitive enhancer for memory and attention, chiefly in elderly patients with mild-to-moderate Alzheimer-type or vascular/cerebrovascular cognitive impairment
- In one positive 6-month multicentre RCT in Alzheimer-type dementia, 1500 mg/day improved psychobehavioural/psychometric measures versus placebo; a separate 3-month RCT at 1000 mg/day found no benefit over placebo
- Reviews note the racetam class's effect on lowering depression/anxiety symptoms may be greater than its effect on memory, but no adequate controlled data support use as an antidepressant or anxiolytic in healthy adults
- No controlled evidence of cognitive benefit in healthy, cognitively intact adults (the typical nootropic-use population)
Adverse effects by system
No specific cardiovascular adverse signal identified in the available small human trials, and no dedicated cardiovascular safety studies exist; cardiovascular safety is effectively unknown, especially with chronic use and in unregulated products.
A pharmacodynamic/pharmacokinetic review reported that aniracetam did not appear to raise liver enzyme levels in trials; however, formal hepatotoxicity data are sparse and long-term hepatic safety is not established.
Aniracetam is not a hormonal agent and there are no human data on hypothalamic-pituitary-testicular/gonadal or other endocrine effects; endocrine impact is unknown (no data).
No human reproductive, fertility, pregnancy or lactation safety data; effects are unknown (no data) and use should be avoided in pregnancy/breastfeeding.
Neuropsychiatric effects are the most concrete human safety concern: a randomized trial reported drug-induced confusion causing treatment discontinuation in aniracetam-treated patients (4 of the aniracetam group vs 1 placebo). Anxiety, agitation, irritability, restlessness and insomnia are described with the racetam class; formal incidence data are lacking.
No evidence of direct nephrotoxicity, but metabolites are renally excreted and accumulate when renal function is reduced (markedly prolonged metabolite half-lives in elderly patients with low creatinine clearance); caution and unknown risk in renal impairment.
No specific hematologic adverse effects reported; no dedicated hematologic safety data exist (no adequate data).
No known dermatologic adverse effects reported in the human literature; data are insufficient to exclude them.
HPTA suppression & recovery
Suppression: None expected / no data
Aniracetam is not an androgen, anabolic steroid or SERM and has no described mechanism for suppressing the hypothalamic-pituitary-gonadal axis; there are no human data on HPTA effects. No SERM or post-cycle intervention is indicated for this compound. Anyone with hormonal concerns or on other agents that do affect the HPTA should consult an endocrinologist rather than self-managing.
Monitoring
Cadence: Baseline before use; re-check renal and hepatic panels within the first few weeks and then periodically (e.g., every few months) during continued use, and promptly if symptoms develop. There is no validated therapeutic monitoring level.
- New or worsening confusion, disorientation, delirium or memory worsening (stop and seek care)
- Marked anxiety, agitation, irritability, insomnia or mood change
- Signs of liver injury: jaundice, dark urine, right-upper-quadrant pain, unusual fatigue, nausea
- Reduced urine output, swelling or other signs of declining kidney function
- Allergic reaction: rash, swelling, difficulty breathing
Contraindications
- Pregnancy and breastfeeding (no safety data)
- Significant renal impairment or advanced age with reduced creatinine clearance (metabolite accumulation; markedly prolonged half-lives)
- Hepatic impairment (compound relies on extensive hepatic first-pass metabolism; safety not established)
- History of confusion, delirium, agitation, psychosis or other serious neuropsychiatric instability (drug-induced confusion reported in a trial)
- Known hypersensitivity to aniracetam or pyrrolidinone/racetam compounds
- Use of unregulated/'research chemical' product where identity, purity and dose cannot be verified
Interaction profile
- ContraindicatedWith DNP: Additive cardiovascular strain
Check a specific combination in the interaction checker.
Reducing harm & when to stop
- No controlled human data support aniracetam use in healthy adults; benefit is unproven and long-term safety is unknown. Treat any claimed cognitive benefit skeptically.
- Products are typically unregulated 'research chemicals' or supplements with no guarantee of identity, purity or dose; third-party certificate-of-analysis testing reduces but does not eliminate this risk.
- Stop use and seek medical care for new confusion, disorientation, marked anxiety/agitation, or signs of liver or kidney problems (jaundice, dark urine, reduced urination, swelling).
- Higher risk with age and reduced kidney or liver function because active metabolites accumulate; such individuals should avoid self-use and consult a clinician first.
- Do not combine with other CNS-active drugs, stimulants or anticholinergics without clinician review; interaction data are lacking.
- Avoid in pregnancy and breastfeeding due to absence of safety data.
- Get baseline and periodic bloodwork (renal and liver panels) and involve a licensed clinician rather than self-managing; this monograph is not a recommendation to use or a dosing guide.
Citations (13)
Every clinical claim above is tied to a primary source. Overall evidence grade C — graded to the best available evidence for its core claims.
- 01
Aniracetam is a pyrrolidinone nootropic (Ro 13-5057) studied in elderly dementia; a 6-month double-blind RCT in 109 mild-to-moderate Alzheimer-type dementia patients found 1500 mg/day significantly improved psychobehavioural measures vs placebo with reportedly excellent tolerability.
- 02
A randomized double-blind trial of aniracetam 1 g/day for 3 months in 44 Alzheimer-type dementia patients showed NO efficacy difference vs placebo, and treatment was interrupted due to confusion in 4 aniracetam patients vs 1 placebo patient (drug-induced confusion signal).
- 03
In a randomized, double-blind, placebo-controlled crossover trial, aniracetam 1 g/day for 3 months was ineffective for cognitive impairment in chronic psychosyndrome after long-term organic solvent exposure.
- 04
A randomized double-blind trial in 60 elderly patients found aniracetam 1500 mg/day improved several psychometric test scores vs placebo over 2-4 months in primary/vascular mental deterioration.
- 05
Review: aniracetam 1500 mg/day was significantly more effective than placebo at 4 and 6 months and more effective than piracetam in 8 of 18 tests, was generally well tolerated, and did not appear to increase liver enzyme levels.
ReviewPMID 8199398 ↗
- 06
Aniracetam positively modulates AMPA-sensitive and metabotropic glutamate receptors and may facilitate cholinergic transmission (proposed mechanism of action).
ReviewPMID 8199398 ↗
- 07
Aniracetam is described as an AMPA receptor potentiator among pyrrolidinones, a mechanism proposed to underlie cognition-enhancing and possible antidepressant-related effects.
ReviewPMID 15180479 ↗
- 08
Review classifying racetams notes oxiracetam and aniracetam are no longer in clinical use and that the class's effect on lowering depression/anxiety may exceed its effect on improving memory.
ReviewPMID 20166767 ↗
- 09
Multiple-treatments meta-analysis found symptomatic treatment of vascular dementia (a group that includes aniracetam among other agents) was associated with improvement in cognitive dysfunction; aniracetam is not evaluated as an isolated agent.
Meta-analysisDOI 10.1007/s00213-018-4867-y ↗
- 10
Pharmacokinetics in elderly cerebrovascular-disease patients: metabolites (anisic acid, p-methoxyhippuric acid) peaked ~2 h and returned to baseline by ~6 h; metabolite half-life was prolonged 4-7 fold vs young volunteers, with creatinine clearance ~20-30 mL/min, and no clinical side effects observed in this small study.
CohortPMID 9062694 ↗
- 11
Pharmacokinetics in healthy young men: after 400 mg oral aniracetam, parent Cmax ~8.7 ng/mL, Tmax ~0.4 h and plasma elimination half-life ~0.47 h, reflecting extensive first-pass metabolism and very short parent survival.
- 12
N-anisoyl-GABA (4-p-anisamidobutyric acid) is a major active metabolite of aniracetam measured in human plasma after oral dosing.
- 13
Aniracetam and its metabolite N-anisoyl-GABA are quantifiable in human plasma from bioavailability studies in healthy volunteers, consistent with rapid conversion of parent to metabolite.
Last reviewed 2026-07-06 · Verified against PubMed · Educational, not medical advice