title: Phenibut (4-amino-3-phenyl-butyric acid): Availability, prevalence of use, desired effects and acute toxicity.
abstract: There has been a global increase in the availability and use of novel psychoactive substances (NPS) over the last decade. Phenibut (β-phenyl-γ-aminobutyric acid) is a GABAB agonist that is used as an NPS. Here, we bring together published scientific and grey information sources to further understand the prevalence of use, desired effects and acute toxicity of phenibut.
  
  
  
  Using European Monitoring Centre for Drugs and Drug Addiction Internet snapshot methodology, we undertook an English language Internet snapshot survey in May 2015 to gather information on the availability and price of phenibut from Internet NPS retailers. To gather information on prevalence of use, desired effects and/or adverse effects, we searched grey literature (online drug discussion forums) and medical literature (PubMed and abstracts from selected International Toxicology conferences).
  
  
  
  We found 48 unrelated Internet suppliers selling phenibut in amounts ranging from 5 g (US$1.60, £1.01/g) to 1000 kg (US$0.23, £0.14/g). Capsules containing 200-500 mg of phenibut were available in packs of between 6 (US$4.45, £2.80/g) and 360 (US$0.43, £0.27/g). According to the grey literature, phenibut is taken for its anxiolytic and euphoric properties, with tolerance and withdrawal syndromes commonly reported adverse effects. Phenibut is taken orally at an average dose of 2.4 g. Case reports in the medical literature feature users who present to emergency departments heavily sedated or experiencing withdrawal. There have been no reported deaths relating to phenibut use.
  
  
  
  Phenibut is readily available in the UK from Internet sites selling NPS. Its desired and adverse effects appear similar to other gamma-aminobutyric acid receptor agonists. [Owen DR, Wood DM, Archer JRH, Dargan PI. Phenibut (4-amino-3-phenyl-butyric acid): Availability, prevalence of use, desired effects and acute toxicity. Drug Alcohol Rev 2016;35:591-596].
authors.affiliation: Division of Brain Sciences, Imperial College London, London, UK.
authors.forename: David R
authors.initials: DR
authors.lastname: Owen
authors.affiliation: Clinical Toxicology, Guy's and St Thomas' NHS Foundation Trust and King's Health Partners, London, UK.|Faculty of Life Sciences and Medicine, King's College London, London, UK.
authors.forename: David M
authors.initials: DM
authors.lastname: Wood
authors.affiliation: Clinical Toxicology, Guy's and St Thomas' NHS Foundation Trust and King's Health Partners, London, UK.
authors.forename: John R H
authors.initials: JR
authors.lastname: Archer
authors.affiliation: Clinical Toxicology, Guy's and St Thomas' NHS Foundation Trust and King's Health Partners, London, UK. paul.dargan@gstt.nhs.uk.|Faculty of Life Sciences and Medicine, King's College London, London, UK. paul.dargan@gstt.nhs.uk.
authors.forename: Paul I
authors.initials: PI
authors.lastname: Dargan
mesh_terms: D000328:Adult; D005260:Female; D018755:GABA Agonists; D006801:Humans; D013287:Illicit Drugs; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D019966:Substance-Related Disorders / Q000453:epidemiology*; D055815:Young Adult; D005680:gamma-Aminobutyric Acid / Q000031:analogs & derivatives*
chemical_list: D018755:GABA Agonists; D013287:Illicit Drugs; D005680:gamma-Aminobutyric Acid; C008842:4-amino-3-phenylbutyric acid
keywords: GABA; GABAB; NPS; acute toxicity; availability; phenibut; prevalence of use; recreational drug