25B-NBOH
25B-NBOH is a synthetic psychedelic of the substituted phenethylamine class, derived from 2C-B through N-benzylation.1 First synthesized in 2011 by Martin Hansen at the University of Copenhagen, it is a close structural analog of 25B-NBOMe and is reported to share most of its properties, with moderately reduced potency and a shorter duration. It produces visually dominant and stimulating psychedelic effects, acting as a potent serotonin receptor agonist at 5-HT2A and 5-HT2C receptors.1
Contents
Dosage & Duration
Dosage
Produces a strong metallic taste and pronounced mouth and tongue numbness lasting up to an hour after absorption. Must be held sublingually for 15-25 minutes. Not orally active. Insufflation is contraindicated due to documented deaths and hospitalizations in closely related NBOMe compounds.
Duration
Subjective Effects
25B-NBOH produces a stimulating psychedelic experience broadly comparable to other N-benzyl phenethylamines, combining euphoria, enhanced empathy, and a sense of insight with both open- and closed-eye visuals. The state is accompanied by pronounced mental and physical stimulation, and perception is noticeably altered throughout. Alongside its recreational qualities, the experience carries a distinct body load that includes restlessness, muscle tension, and alternating sweating and chills.
Physical
The body load is stimulating and somewhat uncomfortable, with restlessness, muscle tension, sweating and chills, suppressed appetite, and difficulty sleeping while the effects persist.
Stimulation
Uncomfortable
Cognitive
The headspace is euphoric and empathogenic, with a sense of insight and a softening of ego boundaries; confusion can also occur, particularly as effects intensify.
Emotional
Visual
Visual effects occur with eyes both open and closed and include a general brightening of color.
Tactile
Reagent Testing
Loading reagent data
Pharmacology
Pharmacodynamics
25B-NBOH acts as a potent serotonin receptor agonist with notably high selectivity for 5-HT2 receptors.12 It binds with strong affinity at both the 5-HT2A and 5-HT2C receptors, and has been described as one of the most selective agonist ligands for the 5-HT2A receptor.
Pharmacokinetics
Dangerous
Highest riskThese combinations are considered extremely harmful and should always be avoided. Reactions to these drugs taken in combination are highly unpredictable and have a potential to cause death.
Unsafe
AvoidThere is considerable risk of physical harm when taking these combinations, they should be avoided where possible.
Caution
Use cautionThese combinations are not usually physically harmful, but may produce undesirable effects, such as physical discomfort or overstimulation. Extreme use may cause physical health issues. Synergistic effects may be unpredictable. Care should be taken when choosing to use this combination.
Tolerance
Serotonergic psychedelics
Harm Potential
Addiction & Dependence
Psychological
Extremely Low25B-NBOH is generally not described as habit-forming, and repeated use may reduce interest in taking it. Use is commonly characterized as self-regulating.
Toxicity
Acute cardiovascular effects including increased heart rate, elevated blood pressure, abnormal heartbeat, and vasoconstriction occur during intoxication;3 the long-term clinical significance in occasional users is not characterized due to limited research.
Psychosis Risk
Anxiety and paranoia appear to occur more readily than with many other psychedelics, potentially due to the compound's prominent stimulating properties. High doses can lead to states of confusion, amnesia, and general sensory overload. Unpredictable dose-response effects may contribute to psychological risk.
Seizure Risk
Seizures are listed among reported physical effects, though frequency and precipitating conditions are not well characterized due to limited human data.
History & Culture
25B-NBOH was first synthesized and documented in 2011 by Martin Hansen at the University of Copenhagen. The compound is a structural derivative of the phenethylamine psychedelic 2C-B, belonging to the broader family of N-benzyl phenethylamines and sharing close structural relationships with the…
Legality
By Country
References
Source Pages
Citations
- (March 2014). Synthesis and structure-activity relationships of N-benzyl phenethylamines as 5-HT2A/2C agonists. ACS Chemical Neuroscience, 5(3), 243–9. https://doi.org/10.1021/cn400216u1234
- (December 2006). Molecular interaction of serotonin 5-HT2A receptor residues Phe339(6.51) and Phe340(6.52) with superpotent N-benzyl phenethylamine agonists. Molecular Pharmacology, 70(6), 1956–64. https://doi.org/10.1124/mol.106.0287201
- Zawilska JB, Kacela M, & Adamowicz P. (2020). NBOMes–Highly Potent and Toxic Alternatives of LSD. Frontiers in Neuroscience. https://doi.org/10.3389/fnins.2020.000781
- (n.d.). Resolução da Diretoria Colegiada – RDC Nº 254, de 10 de dezembro de 2018. https://bvsms.saude.gov.br/bvs/saudelegis/anvisa/2018/rdc0254_10_12_2018.pdf1
- (n.d.). Neue-psychoaktive-Stoffe-Gesetz (NpSG). https://www.gesetze-im-internet.de/npsg/1
- (2019). § 4 NpSG. https://www.gesetze-im-internet.de/npsg/__4.html1
- (n.d.). Taking the cat-and-mouse game to the next level: different perspectives on the introduction of the German New Psychoactive Substances Act. https://pmc.ncbi.nlm.nih.gov/articles/PMC9632031/1
- (n.d.). Föreskrifter (HSLF-FS 2015:35) om ändring i Läkemedelsverkets föreskrifter (LVFS 2011:10) om förteckningar över narkotika. https://lagen.nu/hslf-fs/2015:3512
- (n.d.). Verordnung des EDI über die Verzeichnisse der Betäubungsmittel (BetmVV-EDI), SR 812.121.11 – Anhang 6 (Verzeichnis e), Nummer 131. https://fedlex.data.admin.ch/filestore/fedlex.data.admin.ch/eli/cc/2011/363/20250515/de/pdf-a/fedlex-data-admin-ch-eli-cc-2011-363-20250515-de-pdf-a.pdf12
- (2014). http://www.legislation.gov.uk/uksi/2014/1106/made. http://www.legislation.gov.uk/uksi/2014/1106/made1
- (n.d.). 21 U.S.C. § 813 – Treatment of Controlled Substance Analogues. https://www.law.cornell.edu/uscode/text/21/8131
Further Reading
Automated synthesisInformation aggregated and synthesized using an autonomous workflow built by Josie Kins.
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