intoxicant.wiki2catechol4school
Layout
Depressant

Phenibut

Also called Fenibut, Phenybut, PhGABA, 4-Amino-3-phenylbutanoic acid, 4-Amino-3-phenylbutyric acid, Citrocard

Original Wikipedia articleen.wikipedia.org/wiki/Phenibut revision used (24 October 2026)

Why a "revision used" link? Anyone can edit Wikipedia at any time, so the article you open today may not say what it said when we read it. This link opens the exact version we read on 24 October 2026, frozen as it was. It is the only way to check that every quote on this page matches its source word for word. Newer versions may correct or change things. When we re-check this page against a newer version, the edit log records it. How we cite

Part of the metabolic pathway of Phenibut. See the timeline on the metabolic highway.

Common dose · Insufflation100–200 mg PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.
Onset10–30 minutes PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.
Total10–16 hours PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.
After-effects6–24 hours PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.

Dosage

When sources disagree, both rows are shown as published. Nothing is averaged or merged.

Insufflation

SourceThresholdLightCommonStrongHeavy
PsychonautWiki25 mg PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.50–100 mg PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.100–200 mg PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.200–350 mg PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.350 mg+ PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.

Oral

SourceThresholdLightCommonStrongHeavy
PsychonautWiki0.25 g PW0.5–1 g PW1–2 g PW2–3.5 g PW3.5 g+ PW
TripSit–300–600 mg TS600–1200 mg TS1200–1800 mg+ TS–

NOTE: This substance has a very fast tolerance raise, and also seems to vary a lot person to person. Start low and work your way up. We would recommend starting with a low dose and working it up every 50-100mg's every two weeks. TS

TripSit dose text

TripSit's factsheet also states its doses as text.

Light: 300-600mg's Common: 600-1200mg Strong: 1200-1800mg+ | NOTE: This substance has a very fast tolerance raise, and also seems to vary a lot person to person. Start low and work your way up. We would recommend starting with a low dose and working it up every 50-100mg's every two weeks. TS

What dose are you on? (self-reported, unverified)
Read this first. These numbers come from anonymous visitors typing in a box. Nobody checks them. People misjudge, mistype, troll, or take untested products of unknown strength. They are not a dose guide and never override the sourced table above. They exist only so the sourced ranges can be compared with what people say they take. If you are deciding what to take, use the sourced table, start low, and read the risks section.
Running self-reports

No reports yet.

Reports are anonymous, one per browser per day per route. Counts under 20 are shown but marked as too few to mean anything. Until accounts launch, reports stay in this browser only.

Duration

Route · sourceOnsetCome-upPeakOffsetTotalAfter-effects
Insufflation · PsychonautWiki10–30 minutes PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.10–30 minutes PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.3–4 hours PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.4–6 hours PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.10–16 hours PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.6–24 hours PW⚠ The source row looks copy-pasted from another route. Check it before relying on it.
Oral · PsychonautWiki1.5–3 hours PW1.5–3 hours PW3–4 hours PW4–6 hours PW10–16 hours PW6–24 hours PW

TripSit factsheet

Onset
30-120 minutes TS
Duration
9-16 hours TS
Aftereffects
1-24 hours TS

Mixing

For best safety practice, don't mix this drug with other depressants.

Why: respiratory depression. PsychonautWiki says:

Quotes from PsychonautWiki, CC BY-SA 4.0.

Acute combinations: what happens when these are taken close together. Entries backed by a medical journal or agency are listed first.

Backed by medical journals

  • Depressants (1,4-Butanediol, 2M2B, alcohol, benzodiazepines, barbiturates, GHB/GBL, methaqualone, opioids) - This combination can result in dangerous or even fatal levels of respiratory depression. These substances potentiate the muscle relaxation, sedation and amnesia caused by one another and can lead to unexpected loss of consciousness at high doses. There is also an increased risk of vomiting during unconsciousness and death from the resulting suffocation. If this occurs, users should attempt to fall asleep in the recovery position or have a friend move them into it.[12] PW⚠ PsychonautWiki lists this combination without a danger rating.

Other documented combinations

  • Dissociatives - This combination can result in an increased risk of vomiting during unconsciousness and death from the resulting suffocation. If a sudden loss of consciousness occurs, users should attempt to fall asleep in the recovery position or have a friend move them into it. PW⚠ PsychonautWiki lists this combination without a danger rating.
  • Stimulants - Phenibut is reported to enhance the positive effects of stimulants as well as reduce jitteriness and anxiety. However, this combination can be dangerous due to the risk of excessive intoxication. Stimulants mask the sedative effects of phenibut; once the stimulant wears off, the depressant effects of phenibut will be significantly increased, leading to intensified disinhibition as well as other effects. If combined, one should strictly limit themselves to a certain dose of phenibut prior to stimulant consumption and not redose. This combination can also potentially result in significant dehydration.[13] PW⚠ PsychonautWiki lists this combination without a danger rating.

Risks and toxicity

Phenibut has a low toxicity relative to dose. However, it is potentially lethal when mixed with depressants like alcohol, benzodiazepines or opioids. PW

Phenibut hydrochloride is highly caustic and in sensitive users can cause intestinal discomfort and diarrhea with some lower digestive tract bleeding. PW⚠ PsychonautWiki itself has flagged this text: citation needed.

Due to the extremely long come up period relative to other substances, some users may experience an urge to redose out of the belief that it is weak or not working. This should be avoided to prevent overdose. PW

It is strongly recommended that one use harm reduction practices when using this substance. PW

Dependence and abuse potential

Phenibut is moderately physically and psychologically addictive, although this usually only occurs with heavy abuse of the substance. PW

Tolerance will develop to the sedative-hypnotic effects within a couple of days of continuous use. After cessation, the tolerance returns to baseline in 7 - 14 days. Withdrawal symptoms or rebound symptoms may occur after ceasing usage abruptly following a few weeks or longer of steady dosing and may necessitate a gradual dose reduction. Withdrawal symptoms include severe anxiety, nervousness, hallucinations, tremors, agitation, dizziness, tension, irritation, rapid heartbeat, fatigue, loss of appetite, nausea, vomiting, psychosis, and insomnia.[14] PW

Phenibut produces cross-tolerance with all GABAgenic depressants, meaning that after its consumption, depressants will have a reduced effect. PW

TripSit factsheet

Avoid
Other CNS depressants such as alcohol TS

Testing

Awaiting sourceReagent reactions and test kit guidance from a harm reduction testing service.

Effects

AnxiolyticSedativeMuscle RelaxantAmnesiaDystaxiaHypnotic TS

Overview

β-Phenyl-γ-aminobutyric acid (also known as Fenibut, Phenybut, Noofen, Citrocard, and commonly as Phenibut) is a lesser-known depressant substance of the gabapentinoid class. Phenibut acts as a receptor agonist for GABA, the major inhibitory neurotransmitter in the brain. It is chemically related to baclofen, pregabalin, and gabapentin.[1][2][3] PW

A derivative of GABA with the addition of a phenyl ring which allows it to cross the Blood Brain Barrier. Is mostly used as an anti-anxiety and anti-insomnia medication. Tolerance and physical dependency builds very quickly. TS

Phenibut, sold under the brand name Anvifen among others, is a central nervous system (CNS) depressant with anxiolytic effects, and is used to treat anxiety, insomnia, and for a variety of other indications. It is usually taken orally (swallowed by mouth), but may be given intravenously.[3][4][5] WP

Side effects of phenibut can include sedation, sleepiness, nausea, irritability, agitation, dizziness, euphoria, and sometimes headache, among others. Overdose of phenibut can produce marked central nervous system depression including unconsciousness. The medication is structurally related to the neurotransmitter γ-aminobutyric acid (GABA), and hence is a GABA analogue. Phenibut is thought to act as a GABAB receptor agonist, similarly to baclofen and γ-hydroxybutyrate (GHB). However, at low concentrations, phenibut mildly increases the concentration of dopamine in the brain, providing stimulatory effects in addition to the anxiolysis.[3][5][6] WP

Phenibut was developed in the Soviet Union and was introduced for medical use in the 1960s. Today, it is marketed for medical use in Russia, Ukraine, Belarus, Kazakhstan, and Latvia. The medication is not approved for clinical use in the United States and most of Europe, but it is sold on the Internet as a supplement and purported nootropic. Phenibut has been used recreationally and can produce euphoria as well as addiction, dependence, and withdrawal. It is a controlled substance in Australia, and it has been suggested that its legal status should be reconsidered in Europe as well. In Germany, phenibut is not approved as a drug and, as a food supplement, is controlled under the German New Psychoactive Substances Act.[3][7][8][9] WP

In a 2023 assessment, the U.S. Food and Drug Administration (FDA) determined that phenibut does not meet the definition of a dietary ingredient, thereby making phenibut supplement products misbranded and illegal for marketing. FDA warning letters had been issued to supplement manufacturers marketing phenibut products as adulterated.[10][11] WP

History

History

Phenibut was synthesized at the A. I. Herzen Leningrad Pedagogical Institute (USSR) by Professor Vsevolod Perekalin's team and tested at the Institute of Experimental Medicine, USSR Academy of Medical Sciences. It was introduced into clinical use in Russia in the 1960s.[3] WP

Phenibut was formally incorporated into Soviet spacecraft medical supplies from 1975 onward "as a means of normalizing the neuropsychological state and improving physiological sleep". Records of medication use among Soviet cosmonauts indicate that phenibut was taken during expeditions to or aboard Salyut 4, Salyut 5, and Salyut 6.[15–20] WP

Other names

Alternate spellings include fenibut and phenybut. It is also sometimes referred to as aminophenylbutyric acid. The word phenibut is a contraction of the chemical name of the drug, β-phenyl-γ-aminobutyric acid. In early publications, phenibut was referred to as fenigam and phenigama. The drug has not been assigned an INN (International Nonproprietary Name).[3][4][5][21][22] WP

Brand names

Phenibut is marketed in Russia, Ukraine, Belarus, and Latvia under the brand names Anvifen, Fenibut, Bifren, and Noofen (Russian: Анвифен, Фенибут, Бифрен and Ноофен, respectively).[4] WP

Availability

Phenibut is approved in Russia, Ukraine, Belarus, Georgia and Latvia for medical use. It is not approved or available as a medication in other countries in the European Union, the United States, or Australia. In countries where phenibut is not a licensed pharmaceutical drug, it is sold online without a prescription as a "nutritional supplement". It is often used as a form of self-medication for social anxiety.[7][8] WP

Pharmacology

Pharmacodynamics

Phenibut acts as a full agonist of the GABAB receptor, similarly to baclofen. It has between 30- and 68-fold lower affinity for the GABAB receptor than baclofen, and, in accordance, is used at far higher doses in comparison. (R)-Phenibut has more than 100-fold higher affinity for the GABAB receptor than does (S)-phenibut; hence, (R)-phenibut is the active enantiomer at the GABAB receptor.[46][47][48] WP⚠ A table follows this text in the source and is not copied here. Open the source to see it.

Phenibut also binds to and blocks α₂δ subunit-containing VDCCs, similarly to gabapentin and pregabalin, and hence is a gabapentinoid. Both (R)-phenibut and (S)-phenibut display this action with similar affinity (Kᵢ = 23 and 39 μM, respectively).[49][50] WP

It is often claimed on websites about nootropics and elsewhere on the internet that phenibut increases dopamine. Three papers published in Russian by Soviet scientists in 1979, 1986, and 1990 report that phenibut increases dopamine in the striatum of rats and in the mouse brain. The mechanism underlying this putative effect is unclear. Structurally, phenibut can also be considered a derivative of phenethylamine, and some research suggests that phenibut antagonizes the action of phenethylamine.[3] WP

Pharmacokinetics

Little information thus far has been published on the clinical pharmacokinetics of phenibut. The drug is reported to be well-absorbed. It distributes widely throughout the body and across the blood–brain barrier. Approximately 0.1% of an administered dose of phenibut reportedly penetrates into the brain, with this said to occur to a much greater extent in young people and the elderly. Following a single 250 mg dose in healthy volunteers, its elimination half-life was approximately 5.3 hours and the drug was largely (63%) excreted in the urine unchanged.[3][5] WP

Some limited information has been described on the pharmacokinetics of phenibut in recreational users taking much higher doses (e.g., 1–3 grams) than typical clinical doses. In these individuals, the onset of action of phenibut has been reported to be 2 to 4 hours orally and 20 to 30 minutes rectally, the peak effects are described as occurring 4 to 6 hours following oral ingestion, and the total duration for the oral route has been reported to be 15 to 24 hours (or about 3 to 5 terminal half-lives).[7][51] WP

Chemistry

Formula
C10H13NO2 PC
CAS number
1078-21-3 PC
Molar mass (g/mol)
179.22 PC
IUPAC name (computed by PubChem)
4-amino-3-phenylbutanoic acid PC
SMILES
C1=CC=C(C=C1)C(CC(=O)O)CN PC
InChIKey
DAFOCGYVTAOKAJ-UHFFFAOYSA-N PC
PubChem CID
14113

User reports

Erowid erowid.org

Listings
Awaiting sourceExperience Vault listing and report categories.
Top stories
Awaiting sourceShort summaries of the most-read reports, each linked, saying only what the report says.

Bluelight bluelight.org

Listings
Awaiting sourceTrip report threads and this substance's discussion forum.
Top stories
Awaiting sourceShort summaries of the most-read reports, each linked, saying only what the report says.

Reddit reddit.com

Listings
Awaiting sourceTrip report posts and the relevant subreddits.
Top stories
Awaiting sourceShort summaries of the most-read reports, each linked, saying only what the report says.

Pop culture

No references added yet.

Add a reference

Registered users can add songs, films, books, shows, games and art about this substance. Link a source that names the substance, such as the work's Wikipedia article, a review or an interview, not only the work itself. Entries are voted on and moderated like every other value on this page.

Opens when accounts launch.

References

  1. Other Wyllie, E., Cascino, G. D., Gidal, B. E., Goodkin, H. P. Wyllie’s Treatment of Epilepsy: Principles and Practice. 17 February 2012
  2. Other Benzon, H., Rathmell, J. P., Wu, C. L., Turk, D., Argoff, C. E., Hurley, R. W. Practical Management of Pain E-Book. 11 September 2013
  3. Journal / agency Lapin, I. Phenibut (β-Phenyl-GABA): A Tranquilizer and Nootropic Drug. CNS Drug Reviews. 7 June 2006. doi:10.1111/j.1527-3458.2001.tb00211.x
  4. Journal / agency Drobizhev MY, Fedotova AV, Kikta SV, Antohin EY. Феномен аминофенилмасляной кислоты. Russian Medical Journal. 2016
  5. Other Ozon Pharm. Fenibut
  6. Other Регистр лекарственных средств России ([Russian Medicines Register]). Фенибут (Phenybutum). 2026-07-20
  7. Journal / agency Owen DR, Wood DM, Archer JR, Dargan PI. Phenibut (4-amino-3-phenyl-butyric acid): Availability, prevalence of use, desired effects and acute toxicity. Drug and Alcohol Review. September 2016. doi:10.1111/dar.12356 · PMID 26693960
  8. Journal / agency Cohen PA, Ellison RR, Travis JC, Gaufberg SV, Gerona R. Quantity of phenibut in dietary supplements before and after FDA warnings. Clinical Toxicology. April 2022. doi:10.1080/15563650.2021.1973020 · PMID 34550038
  9. Other Anlage NpSG - Einzelnorm
  10. Journal / agency Phenibut in Dietary Supplements. 12 July 2023
  11. Journal / agency FDA Acts on Dietary Supplements Containing DMHA and Phenibut. 29 April 2019
  12. Journal / agency Koski, A., Ojanpera, I., Vuori, E. Alcohol and Benzodiazepines in Fatal Poisonings. Alcoholism: Clinical and Experimental Research. July 2002. doi:10.1111/j.1530-0277.2002.tb02627.x
  13. Other The Drug Classroom - Phenibut: Combinations
  14. Other Group, D. W. Encyclopedia of Mind Enhancing Foods, Drugs and Nutritional Substances, 2d ed. 25 February 2015
  15. Other I. P. Neumyvakin, Принципы, методы и средства оказания медицинской помощи космонавтам при полетах различной продолжительности (1982), p. 119
  16. Other Translated from the Russian: “В состав бортовых аптечек и медицинских укладок с 1975 г. включен фенибут в качестве средства, нормализующего нервно-психическое состояние, улучшающего физиологический сон.”
  17. Other I. P. Neumyvakin, Принципы, методы и средства оказания медицинской помощи космонавтам при полетах различной продолжительности (1982), Table 12, pp. 109–110
  18. Other Table 12 is titled “Прием медикаментов членами экипажей космических кораблей” (“Medication intake by spacecraft crew members”) and records phenibut intake by crew members during expeditions related to Salyut 4, Salyut 5, and Salyut 6. The table does not indicate whether phenibut was taken during transit aboard Soyuz spacecraft or while aboard the Salyut stations
  19. Other A. D. Yegorov, Results of Medical Studies During Long-Term Manned Flights on the Orbital Salyut-6 and Soyuz Complex, NASA Technical Memorandum 76014, National Aeronautics and Space Administration, November 1979
  20. Other A NASA translation of a Soviet medical report on the second main Salyut 6 crew states that crew commander Vladimir Kovalyonok (“CC-II”) took phenibut several times during the mission to assist with sleep
  21. Other Elks J. The Dictionary of Drugs: Chemical Data: Chemical Data, Structures and Bibliographies. 14 November 2014
  22. Journal / agency Khaunina RA, Lapin IP. Fenibut, a new tranquilizer. Pharmaceutical Chemistry Journal. 1976. doi:10.1007/BF00760021
  23. Other Verordnung zur Änderung der Anlage des Neue-psychoaktive-Stoffe-Gesetzes und von Anlagen des Betäubungsmittelgesetzes
  24. Other § 4 NpSG
  25. Other Evaluation der Auswirkungen des Neue-psychoaktive-Stoffe-Gesetzes (NpSG): Abschlussbericht
  26. Other Verordnung des EDI über die Verzeichnisse der Betäubungsmittel, psychotropen Stoffe, Vorläuferstoffe und Hilfschemikalien
  27. Other Psychoactive Substances Act 2016
  28. Harm reduction site Erowid Phenibut Vault: Legal Status
  29. Other Alabama List of Controlled Substances
  30. Other Tabella 1(PDF) (in Italian). Ministero della Salute [Ministry of Health]. p.19. Retrieved November 24, 2020
  31. Other Database of licensed phenibut medicines and their legal status under the State Agency of Medicines of the Republic of Latvia. Retrieved August 26, 2023
  32. Other Active Latvian law regarding scheduled and banned substances. Retrieved August 26, 2023
  33. Other https://www.zakonyprolidi.cz/cs/2013-463
  34. Other Par La liste des substances psychotropes. link 2
  35. Other 39/2018. (XI. 8.) EMMI rendelet Az új pszichoaktív anyaggá minősített anyagokról vagy vegyületcsoportokról szóló 55/2014. (XII. 30.) EMMI rendelet módosításáról
  36. Other Gazzetta Ufficiale 11/08/20. 11 August 2020
  37. Other Rinkos Ribojimo Priemonės Fenibutui!
  38. Other V-1431 Dėl Lietuvos Respublikos sveikatos apsaugos ministro 2000 m. sausio 6 d. įsakymo Nr. 5 "Dėl Narko
  39. Journal / agency Bonnet U, Scherbaum N, Schaper A, Soyka M. Phenibut — an Illegal Food Supplement With Psychotropic Effects and Health Risks. Deutsches Arzteblatt International. 5 April 2024. doi:10.3238/arztebl.m2024.0003 · PMID 38377332 · PMC11539871
  40. Other 3.3 Phenibut. 31 October 2017
  41. Other Mass school overdose investigation focuses on banned Russian drug. 22 February 2018
  42. Other EMMI Decree substances or groups of compounds classified as new psychoactive substances. 1 January 2015
  43. Other Le phénibut interdit en France | Le Généraliste
  44. Journal / agency Penzak SR, Bulloch M. Phenibut: Review and Pharmacologic Approaches to Treating Withdrawal. Journal of Clinical Pharmacology. June 2024. doi:10.1002/jcph.2414 · PMID 38339875
  45. Journal / agency Jouney EA. Phenibut (β-Phenyl-γ-Aminobutyric Acid): an Easily Obtainable "Dietary Supplement" With Propensities for Physical Dependence and Addiction. Current Psychiatry Reports. March 2019. doi:10.1007/s11920-019-1009-0 · PMID 30852710
  46. Other GABAb Receptor Pharmacology: A Tribute to Norman Bowery: A Tribute to Norman Bowery. 21 September 2010
  47. Journal / agency Dambrova M, Zvejniece L, Liepinsh E, Cirule H, Zharkova O, Veinberg G, Kalvinsh I. Comparative pharmacological activity of optical isomers of phenibut. European Journal of Pharmacology. March 2008. doi:10.1016/j.ejphar.2008.01.015 · PMID 18275958
  48. Journal / agency Allan RD, Bates MC, Drew CA, Duke RK, Hambley TW, Johnston GA, Mewett KN, Spence I. A new synthesis resolution and in vitro activities of (R)- and (S)-β-Phenyl-Gaba. Tetrahedron. 1990. doi:10.1016/S0040-4020(01)82032-9
  49. Journal / agency Zvejniece L, Vavers E, Svalbe B, Veinberg G, Rizhanova K, Liepins V, Kalvinsh I, Dambrova M. R-phenibut binds to the α2-δ subunit of voltage-dependent calcium channels and exerts gabapentin-like anti-nociceptive effects. Pharmacology, Biochemistry, and Behavior. October 2015. doi:10.1016/j.pbb.2015.07.014 · PMID 26234470
  50. Journal / agency Vavers E, Zvejniece L, Svalbe B, Volska K, Makarova E, Liepinsh E, Rizhanova K, Liepins V, Dambrova M. The neuroprotective effects of R-phenibut after focal cerebral ischemia. Pharmacological Research. November 2016. doi:10.1016/j.phrs.2015.11.013 · PMID 26621244
  51. Journal / agency Schifano F, Orsolini L, Duccio Papanti G, Corkery JM. Novel psychoactive substances of interest for psychiatry. World Psychiatry. February 2015. doi:10.1002/wps.20174 · PMID 25655145 · PMC4329884

Text and values on this page are quoted from PsychonautWiki (CC BY-SA 4.0), Wikipedia (CC BY-SA 4.0), TripSit factsheets, PubChem (public domain). Each value links to the exact revision it came from.