is phenibut legal in the united states?

it is legal to possess but not legal to sell as a supplement. the fda has never approved it as a drug, and the fda says it does not meet the legal definition of a dietary ingredient, so supplements that list it as one are misbranded; the agency sent warning letters on that basis in april 2019. it is not listed in the federal controlled-substance schedules, and the cdc has described it as uncontrolled and legal to possess. no us regulator checks what is in a phenibut product before it is sold.

no safe dose has been established, because no controlled trial a western regulator could evaluate exists. what is documented is harm: us poison centres logged 1,320 exposures from 2009 to 2019, with major effects in 12.6%, coma in 6.2% and three deaths, including one death where phenibut was the only substance. in published toxicity cases nearly half needed intubation. australia banned it in 2018 because the risks outweighed the benefits claimed. those are reported cases, a floor rather than a rate, but they are the whole of the safety record.

what does phenibut withdrawal feel like, and is it dangerous?

in the published cases withdrawal brought anxiety, agitation, insomnia, hallucinations, psychosis and sometimes seizures, starting as soon as two hours after the last dose and often worsening over the first day. in a 2023 review of 25 cases, 44% went to intensive care, 24% were intubated, and every case of abrupt stopping was treated in hospital; the three managed as outpatients tapered slowly. there is no standard treatment protocol, so anyone taking it daily should plan coming off with a doctor rather than stop alone.

is phenibut a supplement?

not lawfully, in the fda’s view. the fda’s phenibut page says it does not meet the statutory definition of a dietary ingredient, because it is not a vitamin, mineral, herb, amino acid or other dietary substance, so any product that declares it as a dietary ingredient is misbranded. products sold online as phenibut supplements anyway were found by lab testing to contain anywhere from 21 mg to 1,164 mg a serving.

is phenibut banned anywhere?

yes. australia placed it in schedule 9 of its poisons standard, the prohibited-substance schedule, from february 1, 2018, after its regulator found no established therapeutic benefit in comparable countries and risks of dependence, abuse and overdose needing hospital care. in the united states it is not federally scheduled, but the fda does not allow it as a dietary supplement ingredient.

Substance evidence

Phenibut

Dependence and withdrawal, from the case record.

page first published 2026-09-08 · last updated 2026-10-13

Not an FDA-approved treatmentSold outside the supplement category5 studies on this page

What Its Legal Status Actually Means

Read this before anything below it. Legal to sell is not the same fact as reviewed, verified, or approved.

Phenibut has never been approved by the FDA for any medical use in the United States and is not a lawful dietary supplement ingredient: the FDA has stated that phenibut does not meet the statutory definition of a dietary ingredient, that products listing it as one are misbranded, and it issued warning letters in April 2019 to Evol Nutrition (Sleep Walker, Red Dawn Liquid), NeuroScience Solutions (Kavinace), and Atomixx (Limitless), with further letters since. It is nevertheless not scheduled under the federal Controlled Substances Act and is legal to possess, so it continues to be sold online as a "nootropic," "GABA supplement," or relaxation product with no content standards. It is a registered prescription medicine in Russia, Latvia, and neighbouring post-Soviet countries (brands Noofen, Anvifen, Fenibut), where typical tablets are 250 mg. Australia scheduled it as a Schedule 9 prohibited substance under the Poisons Standard in February 2018 after adolescent overdoses, banning manufacture, sale, and possession.

Quoted whole from the 2026-08-18 study harvest. Not summarized, not shortened.

is phenibut safe or legal? what the case reports and the regulators say

there is no fda label for phenibut, because no phenibut product has ever been approved in the united states for any use. the legal facts below are read from the fda’s phenibut page in its dietary supplement ingredient directory (content current as of july 12, 2023), the fda’s april 16, 2019 constituent update and one of the three april 10, 2019 warning letters it links, 21 cfr part 1308 as published on ecfr on 2026-10-13, and the australian therapeutic goods administration’s october 2017 final scheduling decision, read in archived form because the tga site did not respond. every case and poison-centre figure is from a study record on this page, each of which is a library row linked at the end, re-read against its pubmed abstract or full text on 2026-10-13. every source is linked at the end of this section. last checked 2026-10-13.

phenibut is a drug developed in the soviet union in the 1960s as an antianxiety medicine, still registered as a prescription medicine in russia and neighbouring countries, and sold online in the united states as a "nootropic", sleep aid or relaxation powder [status; graves-2020]. it acts on gaba b receptors, the same target as the muscle relaxant baclofen, which is why it sedates and why people who take it daily can become dependent on it [risks; feldman-2023]. the short answers to the questions people search: it is not an approved drug in the united states, the fda says it is not a lawful dietary supplement ingredient, it is not a federally controlled substance, australia banned it in 2018, there is no controlled trial of it for anxiety or sleep in any western journal, and the medical record on it is a record of emergency cases. this section says what each of those legal facts means, what the human evidence is and is not, what the case reports and poison-centre data found about overdose and withdrawal, and what lab testing found in the products. every number is from a study record on this page or a regulator’s own document, and each source is linked at the end.

this is information to take to a prescriber or pharmacist. nothing here tells anyone to take phenibut or to stop it. stopping after daily use can bring on a withdrawal that has needed intensive care, so for anyone already taking it every day, how to come off is a medical question, not a do-it-yourself one.

is phenibut legal? what each regulator has said

not approved: the fda has never approved phenibut as a medicine for any use [status; cohen-2022]. not a supplement: the fda’s position, on its phenibut page, is that phenibut "does not meet the statutory definition of a dietary ingredient", because the law limits dietary ingredients to vitamins, minerals, herbs and other botanicals, amino acids, dietary substances that add to the diet, and concentrates or extracts of those, and "because phenibut does not fit any of the categories of dietary ingredients under the fd&c act, any dietary supplements that declare phenibut as a dietary ingredient are misbranded" [fda-page]. on april 10, 2019 the agency sent warning letters on that basis to three sellers of products labelled as supplements, noting that phenibut was "sometimes marketed for uses such as a sleep aid", and gave them 15 working days to say how they would comply [fda-2019; fda-letter]. the letters add a footnote worth reading exactly: they do "not address whether phenibut can be lawfully marketed in dietary supplements as non-dietary ingredients", which would require a food additive regulation or a finding that it is generally recognised as safe; no such regulation or finding is cited anywhere in the fda’s phenibut material [fda-letter; fda-page].

not controlled: phenibut does not appear in the federal schedules of controlled substances in 21 cfr part 1308 as published on 2026-10-13 [cfr], and the cdc’s 2020 report put it plainly: "phenibut is uncontrolled and legal to possess in the united states" [graves-2020]. so the honest summary of us law is three separate facts: it is not an approved drug, it is not a lawful supplement ingredient, and possessing it is not a federal crime. legal to buy online is not the same fact as reviewed, approved or dose-checked, and no us regulator checks what is in a phenibut product before it is sold.

banned in australia: the australian therapeutic goods administration’s scheduling delegate decided on october 31, 2017 to place phenibut in schedule 9 of the poisons standard, the prohibited-substance schedule, from february 1, 2018 [tga-2017]. the delegate’s reasons are a regulator’s summary of the evidence: phenibut is used therapeutically in russia, but "the associated clinical trial literature is unable to be evaluated critically at this time due to translation issues", there "has been no established therapeutic benefit of phenibut in regulatory comparable countries", the risks include "tolerance, dependence, abuse, accidental and intentional overdose resulting in significant toxicity requiring hospitalisation", and "the perceived benefits (as indicated in public submissions) are substantially outweighed by the risks" [tga-2017].

does phenibut work for anxiety? what the evidence is

in favour, stated as strongly as the record allows. phenibut is a registered prescription medicine in russia, latvia and neighbouring countries, sold as 250 mg tablets, and is used there for anxiety, insomnia and alcohol withdrawal [status; cohen-2022]. the russian clinical literature exists, people describe benefit in public submissions to regulators, and in the minnesota poison-centre series 23% of people said they took it to treat anxiety [tga-2017; mccabe-2019]. that is the case for it: a long history of prescription use in one region and a reported reason for use.

against. the 2026-08-18 study harvest searched pubmed for controlled trials of phenibut and found only russian-language papers that could not be obtained in full or verified, none a placebo-controlled report of anxiety or depression outcomes; no systematic review or meta-analysis of any trial exists [exclusions]. the two systematic reviews that do exist searched the medical databases and found case reports and conference abstracts only, "no controlled studies" [weleff-2023; feldman-2023]. the australian regulator reached the same place in 2017: the trial literature could not be critically evaluated and no therapeutic benefit had been established in comparable countries [tga-2017]. so whether phenibut helps anxiety at a dose that is safe, compared with placebo or with treatments that have been tested, has not been shown in any trial a western regulator has been able to read. that absence is the finding, and it is not a finding of safety.

what the emergency record shows: overdose

the national number: from 2009 to 2019, us poison centres took calls about 1,320 phenibut exposures from all 50 states and the district of columbia, 85% of them from health care facilities, 75.5% in men, mostly aged 18 to 34. drowsiness or lethargy was reported in 29.0%, agitation in 30.4%, a racing heart in 21.9% and confusion in 21.3%; coma in 80 cases (6.2%); and major effects, meaning life-threatening or causing significant disability, in one in eight (12.6%). three people died. among exposures where phenibut was the only substance involved, 10.2% still had major effects, including one death [graves-2020]. the numbers rose sharply after 2015, partly because "phenibut" only became a searchable term in the poison-centre database that year, and they are a floor, not a rate: exposures are reported by callers, no commercial lab test exists, and phenibut "is not detected on routine urine drug screens", so emergency doctors often cannot confirm it [graves-2020].

the clinical detail: in the minnesota poison-centre series, 56 calls from 2000 to 2018, 48 of them (85.7%) came in the last five years, more than half of patients had central nervous system effects, and 11 (19.6%) needed a breathing tube; no one died, and other substances were documented in 35.7% [mccabe-2019]. the 2023 systematic review of 62 published cases found that 48.7% of the toxicity cases needed intubation, that the commonest features were altered consciousness, sleepiness, psychosis and movement disorders, that 86.8% of people had bought it online, and that 63.2% also used other addictive substances, most often benzodiazepines and alcohol; average hospital stays were 5.0 days for toxicity [weleff-2023]. the mechanism is the reason combinations matter: phenibut is a central nervous system depressant, and alcohol, benzodiazepines, opioids and other sedatives add to the same breathing suppression [risks].

what the emergency record shows: dependence and withdrawal

dependence came fast in the published cases. the 2023 withdrawal review screened 515 articles and found 25 usable cases, all case reports or conference abstracts: the shortest use before withdrawal was one week at 2 to 3 g a day, the median daily dose before withdrawal was 10 g, forty times a 250 mg russian tablet, and symptoms began as soon as two hours after the last dose [feldman-2023]. 16 of the 25 (64%) got worse within the first 24 hours after reaching care, 2 (8%) had seizures, 6 (24%) were intubated, 11 (44%) went to intensive care, and 19 (76%) needed at least two drugs to control symptoms. every published case of abrupt stopping was admitted to hospital; the three cases managed as outpatients (12%) all used a slow phenibut taper [feldman-2023]. the other review found that 95.7% of withdrawal cases involved daily use, that the commonest symptoms were anxiety, irritability or agitation, insomnia and psychosis, that 69.6% needed several medicines, and that withdrawal stays averaged 7.7 days [weleff-2023].

what that does and does not mean. both reviews say there is no standard treatment protocol; the withdrawal review recommends consulting toxicologists or addiction specialists [feldman-2023; weleff-2023]. these are case reports: they show what phenibut withdrawal can do, not how often it happens, they come from people sick enough to reach a hospital and be written up, and the doses people believed they took may not match what the product contained [feldman-2023; weleff-2023]. the right reading is not that everyone who stops will need intensive care. it is that nobody can predict who will, and that the only people in the literature who came off outside hospital did it gradually and under medical care.

what is in the products

researchers bought four brands labelled as supplements containing phenibut before and after the fda’s 2019 warnings and measured them by mass spectrometry. before the warnings, two of the four contained phenibut, at 484 and 487 mg per serving. after the warnings, all four did, from 21 mg to 1,164 mg per serving; two contained it only after the warnings, the amount went up in three of the four, and the largest dose was as much as 450% greater than a typical 250 mg russian pharmaceutical tablet [cohen-2022]. four brands is a small snapshot, not a market survey, but it is the measured version of the risk the harvest records: a person buying phenibut online does not know the dose they are taking, and a serving can differ more than fifty-fold between products [cohen-2022; risks].

questions for a prescriber or pharmacist about phenibut

each one comes from a warning or a study above. they are questions, not instructions; the answers depend on a history nobody here has.

i have been taking phenibut every day. the published withdrawal cases needed hospital care when people stopped abruptly, and the few managed outside hospital tapered slowly. what would a safe plan to come off look like for me, and who should supervise it?
i take it with alcohol, a benzodiazepine, an opioid, gabapentin or a sleep medicine. how much does that add to the risk of my breathing slowing down?
the products tested ranged from 21 mg to 1,164 mg a serving. how would either of us know what dose i have actually been taking?
phenibut does not show up on a routine urine drug screen. if i ever end up in an emergency department, what should the people treating me be told?
i started phenibut for anxiety or sleep. there is no controlled trial of it for either in a western journal. which treatments for my anxiety or sleep have been tested, and what would they involve?
is anything i take now, prescribed or bought, acting on the same gaba receptors?

questions people ask

is phenibut legal in the united states?: it is legal to possess but not legal to sell as a supplement. the fda has never approved it as a drug, and the fda says it does not meet the legal definition of a dietary ingredient, so supplements that list it as one are misbranded; the agency sent warning letters on that basis in april 2019. it is not listed in the federal controlled-substance schedules, and the cdc has described it as uncontrolled and legal to possess. no us regulator checks what is in a phenibut product before it is sold.
is phenibut safe?: no safe dose has been established, because no controlled trial a western regulator could evaluate exists. what is documented is harm: us poison centres logged 1,320 exposures from 2009 to 2019, with major effects in 12.6%, coma in 6.2% and three deaths, including one death where phenibut was the only substance. in published toxicity cases nearly half needed intubation. australia banned it in 2018 because the risks outweighed the benefits claimed. those are reported cases, a floor rather than a rate, but they are the whole of the safety record.
what does phenibut withdrawal feel like, and is it dangerous?: in the published cases withdrawal brought anxiety, agitation, insomnia, hallucinations, psychosis and sometimes seizures, starting as soon as two hours after the last dose and often worsening over the first day. in a 2023 review of 25 cases, 44% went to intensive care, 24% were intubated, and every case of abrupt stopping was treated in hospital; the three managed as outpatients tapered slowly. there is no standard treatment protocol, so anyone taking it daily should plan coming off with a doctor rather than stop alone.
does phenibut work for anxiety?: it has not been shown to. it is a prescription medicine in russia, used there for anxiety, but the russian trial literature could not be critically evaluated by australia’s regulator, and searches of the medical databases have found no placebo-controlled trial of anxiety outcomes in a western journal, and no systematic review of any trial. the systematic reviews that exist found only case reports of harm. that is an absence of evidence of benefit, not evidence of safety.
is phenibut a supplement?: not lawfully, in the fda’s view. the fda’s phenibut page says it does not meet the statutory definition of a dietary ingredient, because it is not a vitamin, mineral, herb, amino acid or other dietary substance, so any product that declares it as a dietary ingredient is misbranded. products sold online as phenibut supplements anyway were found by lab testing to contain anywhere from 21 mg to 1,164 mg a serving.
is phenibut banned anywhere?: yes. australia placed it in schedule 9 of its poisons standard, the prohibited-substance schedule, from february 1, 2018, after its regulator found no established therapeutic benefit in comparable countries and risks of dependence, abuse and overdose needing hospital care. in the united states it is not federally scheduled, but the fda does not allow it as a dietary supplement ingredient.

sources for this section

the library rows link to our one-page summary of each study, with the original paper, its funding and our evidence grade on that page.

What the Research Shows

5 records from the 2026-08-18 harvest, each checked against PubMed and Europe PMC on that date. How a study was designed, how many people were in it, and who paid for it are printed above what it found, because those three facts decide how much the finding is worth.

Study 1 · 2023
- Systematic review of observational studies
- 62 participants
- Reputable journal
- Funding not established
- Declared conflicts of interest
moderate60/100
Reasonable evidence with real limitations.
Read this first: This is a systematic review of case reports, not of trials. Case reports capture only the people who reached a hospital and were written up, so they show what phenibut can do but cannot tell you how often it does it.
A systematic search of Medline, Embase, and the Cochrane Library found 62 published cases of phenibut toxicity or withdrawal across 36 reports and no controlled trials at all. Nearly half of the toxicity cases (48.7%) required intubation, the most common presentations were altered mental status, somnolence, psychosis, and movement disorders, and 95.7% of the withdrawal cases involved daily use; average hospital stays were 5.0 days for toxicity and 7.7 days for withdrawal, and about 87% of people had bought the drug online.
Weleff J, Kovacevich A, Burson J, Nero N, Anand A. (2023). Clinical Presentations and Treatment of Phenibut Toxicity and Withdrawal: A Systematic Literature Review. Journal of Addiction Medicine. PMID 37579098.
How this record was checked
PubMed record 37579098 fetched via NCBI efetch 2026-08-18; title, authors, journal, year, DOI, and the figures of 62 cases from 36 studies confirmed from the abstract. The PubMed record carries the conflict-of-interest statement "The authors report no conflicts of interest." Europe PMC core record checked 2026-08-18: no grant or funding statement available, so funding recorded UNKNOWN.
Study 2 · 2023
- Systematic review of observational studies
- 25 participants
- Reputable journal
- Funding not established
early signal54/100
Suggestive but preliminary. Not settled.
Read this first: The authors state plainly that the whole data set is case reports and is therefore subject to publication bias, that reported doses may not reflect what unregulated products actually contained, and that people describing single-substance use may have been using other drugs too.
A PRISMA systematic review screened 515 articles and found 25 usable published phenibut withdrawal cases — all case reports or conference abstracts, no controlled studies. The shortest use before withdrawal was one week at 2-3 g/day, the median daily dose was 10 g, withdrawal began as soon as two hours after the last dose, 64% worsened within 24 hours of reaching care, 24% were intubated, 44% went to the ICU, and 76% needed at least two drugs to control symptoms. Every abrupt-cessation case was admitted as an inpatient.
Feldman R, Autry B, Dukes J, Lofy T, Marchetti G, Patt A, Batterman N, Theobald J. (2023). A systematic review of phenibut withdrawal focusing on complications, therapeutic approaches, and single substance versus polysubstance withdrawal. Clinical Toxicology. PMID 38112312.
How this record was checked
PubMed record 38112312 fetched via NCBI efetch 2026-08-18; title, all eight authors, journal, year, DOI, and the figures of 515 screened / 25 included cases confirmed from the abstract. Europe PMC core record checked 2026-08-18: no grant or funding statement available and no conflict-of-interest statement in the record, so funding recorded UNKNOWN and conflicts false.
Study 3 · 2020
- Cross-sectional study
- 1,320 participants
- Government body
- Funding not established
- Declared conflicts of interest
moderate56/100
Reasonable evidence with real limitations.
Read this first: Poison-centre data are passive surveillance: exposures are self-reported by callers, are not laboratory-confirmed (phenibut is not detected on routine urine drug screens), and most people who use phenibut never call, so these numbers are a floor, not an incidence rate. Some of the rise after 2015 reflects "phenibut" being added as a searchable term that year.
CDC analysis of the National Poison Data System found 1,320 phenibut exposure calls from all 50 states between 2009 and 2019, rising sharply after 2015; 85% came from healthcare facilities and 75.5% involved men, mostly aged 18-34. Coma was reported in 80 cases (6.2%), major effects — life-threatening or causing significant disability — in 12.6%, and three people died; among cases where phenibut was the only substance involved, 10.2% still had major effects and one died.
Graves JM, Dilley J, Kubsad S, Liebelt E. (2020). Notes from the Field: Phenibut Exposures Reported to Poison Centers - United States, 2009-2019. MMWR Morbidity and Mortality Weekly Report. PMID 32881852.
How this record was checked
PubMed record 32881852 fetched via NCBI efetch 2026-08-18; title, authors, journal, year, and DOI confirmed. Full text fetched from Europe PMC (PMC7470459) 2026-08-18: N=1,320 exposures, 85.0% healthcare-facility calls, 6.2% coma, 12.6% major effects, three deaths, and 10.2% major effects in single-substance cases all read directly off the article; the record is flagged is-retracted: no. The article carries an ICMJE conflict-of-interest disclosure (none disclosed) but no funding statement, so funding recorded UNKNOWN.
Study 4 · 2019
- Case series
- 56 participants
- Reputable journal
- Funding not established
contested39/100
Weak or heavily disputed. Treat as a question, not an answer.
Read this first: A single-state case series of 56 calls, with coingestants documented in 36% of patients, cannot separate phenibut's effects from other drugs and cannot estimate how common these outcomes are among people who use phenibut. It scores low on the evidence rubric by design — it is a description of hospital cases, not a study of whether phenibut helps or harms.
The Minnesota Poison Control System logged 56 phenibut exposure calls over 19 years, but 48 of them (85.7%) came in the last five years of that span. Over half of patients had central nervous system effects and 11 (19.6%) required intubation for respiratory failure; 23% said they were using phenibut to treat anxiety and 48% were classified as abuse. No deaths occurred in this series.
McCabe DJ, Bangh SA, Arens AM, Cole JB. (2019). Phenibut exposures and clinical effects reported to a regional poison center. American Journal of Emergency Medicine. PMID 30878413.
How this record was checked
PubMed record 30878413 fetched via NCBI efetch 2026-08-18; title, authors, journal, year, DOI, and the figures N=56, 85.7% in five years, 19.6% intubated, 48% abuse, 23% anxiety confirmed from the abstract. Europe PMC core record checked 2026-08-18: no grant or funding statement and no conflict-of-interest statement available, so funding recorded UNKNOWN and conflicts false.
Study 5 · 2022
- Cross-sectional study
- 4 participants
- Reputable journal
- Funding not established
early signal42/100
Suggestive but preliminary. Not settled.
Read this first: Only four brands met the inclusion criteria, so this is a small snapshot rather than a market-wide survey; it demonstrates that labelled dose cannot be trusted, not the exact proportion of products that are mislabelled.
Researchers bought four brands of supplements labelled as containing phenibut before and after the FDA's 2019 warnings and analysed them by mass spectrometry. Before the warnings only two of four actually contained phenibut; afterwards all four did, at 21 mg to 1,164 mg per serving — up to 450% more than a 250 mg Russian pharmaceutical tablet — and the quantity had increased in three of the four products.
Cohen PA, Ellison RR, Travis JC, Gaufberg SV, Gerona R. (2022). Quantity of phenibut in dietary supplements before and after FDA warnings. Clinical Toxicology. PMID 34550038.
How this record was checked
PubMed record 34550038 fetched via NCBI efetch 2026-08-18; title, authors, journal, year, DOI, and the dose figures (484/487 mg before; 21-1,164 mg after; up to 450% of a 250 mg tablet) confirmed from the abstract. Europe PMC core record checked 2026-08-18: no grant or funding statement and no conflict-of-interest statement available, so funding recorded UNKNOWN and conflicts false.

The Risks

Nobody checks this purchase the way a prescription is checked. No prescriber reviews it against the rest of what you take, no pharmacist screens the interaction, and no regulator confirms the dose in the capsule before it is sold. That is why this section sits here at full length rather than as a footnote.

What the paragraph below covers:

Slowed breathing
Psychosis and mania
Dependence and withdrawal
Drug interactions
What is actually in the product
Sedation

Phenibut is a GABA-B receptor agonist, pharmacologically closer to baclofen and GHB than to any supplement, and it produces tolerance and physical dependence fast: in the published withdrawal literature the shortest documented time to withdrawal was one week of use at 2-3 g per day, and the median daily dose people had escalated to before withdrawal was 10 g — forty times a Russian pharmaceutical tablet. Withdrawal is not mild. Published cases include delirium, hallucinations, psychosis, severe agitation, seizures, intubation in about a quarter of cases, and ICU admission in about 44 percent; every published case of abrupt cessation was managed as an inpatient, most needed two or more drugs to control symptoms, and there is no standard treatment protocol. In overdose, phenibut causes profound sedation and respiratory depression; roughly one in five people in a regional poison-centre series required intubation, and US poison centres logged three deaths among 1,320 exposures over 2009-2019. Because it is not detected on routine urine drug screens and no commercial assay exists, emergency clinicians frequently cannot confirm it. Products sold online have been found to contain anywhere from 21 mg to 1,164 mg per serving, so users routinely do not know their dose. Combining phenibut with alcohol, benzodiazepines, opioids, or other sedatives compounds respiratory depression, and there is no controlled-trial evidence that it safely or effectively treats anxiety, insomnia, or any other mental health condition.

What Is Not Known

The boundaries of the section above, in the harvest’s own words. What it excluded, why, and where it looked and found nothing. An absence of evidence is not evidence of absence, and it is not evidence of benefit either.

What Was Left Out, and Why

Quoted from the harvest, where these notes sat above the study list rather than after it. Where a note says “below” it means the studies in the section above.

No meta-analysis or systematic review of RCTs exists for phenibut in any Western indication. A PubMed search for phenibut AND (randomized OR randomised OR clinical trial) run 2026-08-18 returned 12 records; the only ones describing controlled human treatment studies are Russian-language papers in Zh Nevrol Psikhiatr Im S S Korsakova (e.g. PMIDs 29265084, 28805758, 27029450, 25591517) that were not obtainable in full text, are not placebo-controlled reports of anxiety or depression outcomes, and could not be verified end-to-end. They are therefore dropped, not guessed at. The complete absence of quality controlled efficacy evidence is the finding here.
Individual phenibut case reports (BMJ Case Rep 23391959, Case Rep Psychiatry 29854531, WMJ 35442585, Pediatr Neonatol 35927183, and roughly 30 others) excluded in favour of the two systematic reviews below, which subsume them.
Owen 2016 (Drug Alcohol Rev, PMID 26693960, internet-availability snapshot) excluded as a grey-literature survey superseded by the poison-centre data included here.

The Retraction Check

PubMed efetch records for all five PMIDs fetched 2026-08-18 and inspected for "Retraction in", "Erratum", "Expression of concern", and "Withdrawn" flags; none present. Europe PMC core records show no correction/retraction entries.

Questions for a Prescriber or Pharmacist

This page does not tell anyone to take Phenibut or to avoid it. It is not able to: it does not know what else you take, what you have tried, or what you are treating. These are the questions each study above raises, written to be asked out loud.

I've been taking phenibut I bought online — given that the entire medical literature on it is emergency cases and not trials, how do we get me off it safely and what would we treat my anxiety or sleep with instead?
If I stop phenibut suddenly, published cases show people needing intensive care — can we plan a supervised taper rather than my stopping on my own?
Phenibut sends people to US poison centres more than a hundred times a year and has been linked to deaths even when taken alone — is there any reason for me to keep taking it instead of a treatment you can monitor?
About a quarter of the people in this poison-centre series were taking phenibut for anxiety and one in five needed a breathing tube — what proven anxiety treatment could I use instead?
Lab testing found phenibut supplements containing anywhere from 21 mg to over 1,100 mg per serving with no way to tell from the label — how would either of us know what dose I've actually been taking?

And the one to ask at the counter, whatever the answers above turn out to be: given everything I am already taking, what would you want to know about Phenibut before I put it in the same body?

Open Phenibut in veisund

The app has the resources behind this page and people working through the same questions.What you post there goes to people, not to a model. If someone answers, it is a person who has been there. The one automated message is a crisis-resource reply.

Where This Page Comes From

Transcribed from the study-harvest-2026-08-18 record for phenibut, built into this page by scripts/supplement-ingest.mjs on 2026-09-07. Nothing here is fetched at page load, and nothing here was written by a model without a citation behind it.

Source file	study-harvest/2026-08-18/phenibut.yaml
Source repo	REPTechnologies/avalo-backend
SHA-256	fbed38121b164a2e3f9bf018225c26d318a3d2f196ed37a0c000f6079337260c
Also searched as	Noofen, Anvifen, Fenibut, beta-phenyl-GABA, 4-amino-3-phenylbutyric acid, phenygam

The Other Substances

Do any supplements actually work? asks the question across all of them. The full library has the medication records, the funding investigations, and the glossary.