From PsychonautWiki
(Redirected from 2-cb)
Jump to navigation Jump to search
Summary sheet: 2C-B
Chemical Nomenclature
Common names 2C-B, Nexus, Bees
Substitutive name 4-Bromo-2,5-dimethoxyphenethylamine
Systematic name 2-(4-Bromo-2,5-dimethoxyphenyl)ethanamine
Class Membership
Psychoactive class Psychedelic
Chemical class Phenethylamine
Routes of Administration

WARNING: Always start with lower doses due to differences between individual body weight, tolerance, metabolism, and personal sensitivity. See responsible use section.

Threshold 5 mg
Light 10 - 15 mg
Common 15 - 25 mg
Strong 25 - 45 mg
Heavy 45 mg +
Total 5 - 8 hours
Onset 20 - 40 minutes
Come up 40 - 60 minutes
Peak 2 - 3 hours
Offset 1.5 - 3 hours
After effects 2 - 4 hours

DISCLAIMER: PW's dosage information is gathered from users and resources for educational purposes only. It is not a recommendation and should be verified with other sources for accuracy.


4-Bromo-2,5-dimethoxyphenethylamine (also known as Nexus, Bromo Mescaline, BDMPEA, Venus, and 2C-B) is a psychedelic substance of the phenethylamine class. 2C-B is the most well-known member of the 2C-x family of psychedelic phenethylamines, which are closely related to the classical psychedelic mescaline. It is thought to produce its psychoactive effects by activating serotonin receptors in parts of the brain, although the precise mechanism is not fully understood.

2C-B was first discovered in 1974 by the American chemist Alexander Shulgin, who documented its synthesis and subjective effects in his 1991 book PiHKAL ("Phenethylamines I Have Known and Loved").[1][2] In the 1970s, it was used in patients by a small number of psychotherapists in the United States and was considered one of the best substances for this purpose due to its short duration, relative absence of side effects, and comparably mild nature.[3] It entered into recreational use shortly afterwards and was manufactured and sold commercially under names such as "Eros" and "Nexus" in head/smart shops and adult video stores before becoming federally prohibited by the DEA in 1995.[4]

Subjective effects include open and closed-eye visuals, time distortion, euphoria, and ego loss. User reports typically describe the effects of 2C-B as moderate, warm, and highly sensual. It is usually described as having a less serious or grandiose headspace than LSD or psilocybin mushrooms, with a greater emphasis on visual and tactile effects. Smaller doses can be used as a sensory and aesthetic enhancer (in a manner somewhat similar to MDMA) while larger doses produce a distinct classical psychedelic effect.

2C-B is considered to be physiologically well-tolerated and likely has a safety profile similar to classical psychedelics (known to have low toxicity). However, more research is needed to fully understand the toxicity and health risks of 2C-B. It is highly advised to use harm reduction practices if using this substance.

History and culture

2C-B was first synthesized and tested for psychoactivity in 1974 by Alexander Shulgin, who was in search of novel psychedelic compounds based on the chemical structure of mescaline. His findings were later published in his 1991 book PiHKAL, in which it was listed among the "magical half-dozen" of psychedelic phenethylamines that he deemed most important.[5] The list consists of mescaline, DOM, 2C-B, 2C-E, 2C-T-2, and 2C-T-7.[6] In interviews, Alexander Shulgin repeatedly declared it his favorite psychedelic trip.[7]

In the 1970s, 2C-B was used in patients by a small number of psychotherapists in the United States. These therapists reported that it created a warm, empathetic bond between them and their patients, helping to break down their ego defenses and inner resistances and allowing the patient to get in touch with suppressed emotions and repressed memories.[8] The gentle nature of 2C-B, in addition to its mild side effects and short duration, were found to be desirable traits for a therapeutic setting.

Shortly after gaining traction in the underground psychotherapy community, 2C-B became popular in the recreational drug scene. 2C-B was well-liked as a MDMA substitute in raves and parties due to its minimal comedown and a clear, euphoric headspace. In the 1980s and early 1990s, several foreign companies legitimately manufactured 2C-B under the brand names "Nexus", "Erox", and "Performax" and advertised that it would alleviate impotence, frigidity, and diminished libido. It was sold at adult book and video stores, "head" shops, and some nightclubs. The DEA reported its distribution in Miami, Florida as yellow pills marketed as an aphrodisiac.[citation needed]

In the United States, 2C-B gained popularity as an alternative to MDMA following its classification as a Schedule I substance in 1985. Its increasing popularity led it to be placed in Schedule I in 1995.[9] It saw a resurgence in interest in the 2000s, with the advent of the research chemicals scene and darknet markets.

2C-B was legally sold in Southern Africa from 1993 to early 1996. It was marketed as medicine for Sangomas (traditional healers) under the name "Ubulawu Nomathotholo", which roughly translates to "Medicine of the Singing Ancestors".[10][11][12]



This chemistry section is incomplete.

You can help by adding to it.

2C-B, or 2,5-dimethoxy-4-bromophenethylamine, is a substituted phenethylamine. Substituted phenethylamines are a chemical class of organic compounds that are based upon the phenethylamine structure, a phenyl ring bound to an amino (NH2) group through an ethyl chain. 2C-B possesses methoxy functional groups CH3O- attached to carbons R2 and R5 as well as a bromine atom attached to carbon R4 of the phenyl ring.

2C-B belongs to the 2C family of phenethylamines, all of which possess methoxy groups on the 2 and 5 positions of the benzene ring.[13]


Pill bottle-o.png

This pharmacology section is incomplete.

You can help by adding to it.

Further information: Serotonergic psychedelic

Unlike most psychedelics, 2C-B has been shown to be a low efficacy serotonin 5-HT2A receptor partial agonist[14] or even full antagonist.[15] This suggests that the 5-HT2C receptor is primarily responsible for mediating the effects experienced by users of 2C-B.[16] Research also suggests that 2C-B increases dopamine levels in the brains of rats which may contribute to its psychoactivity.[17]

However, the role of these interactions and how they result in the psychedelic experience continues to remain elusive.

Subjective effects

Disclaimer: The effects listed below cite the Subjective Effect Index (SEI), a literature which relies on collected anecdotal reports and the personal experiences of PsychonautWiki contributors. As a result, they should be taken with a healthy amount of skepticism. It is worth noting that these effects will not necessarily occur in a consistent or reliable manner, although higher doses (common+) are more likely to induce the full spectrum of reported effects. Likewise, adverse effects become much more likely with higher doses and may include serious injury or death.

Physical effects

Visual effects

Cognitive effects

Multi-sensory effects

Transpersonal effects

Combinational effects

  • Cannabis - Cannabis majorly intensifies and extends both the sensory and cognitive effects of 2C-B. Extreme caution should be exercised with this combination as it can also elevate the anxiety, confusion and psychosis risk of cannabis.
  • Dissociatives - When combined with dissociatives, the geometry, euphoria, dissociation and hallucinatory effects are often greatly enhanced. Dissociative-induced holes, spaces, and voids while under the influence of 2C-B have significantly more vivid visuals than dissociatives alone. It also results in more intense internal hallucinations and corresponding confusion which can develop into delusions and psychosis.
  • Nitrous - Nitrous oxide is commonly used in combination with psychedelics. The two are known to possess powerful cross-synergistic effects, including the capacity to send the user directly into an "ego death" state. The speed and intensity with which this occurs is very rapid and the euphoria that can result often leads to the urge to compulsively redose.
  • MDMA - When combined with MDMA, the physical and cognitive effects of 2C-B become strongly amplified. The visual, physical and cognitive effects of 2C-B are also intensified with strong sensations of euphoric pleasure manifested through distinct body highs and headspaces, and uniquely colorful visuals. The synergy between these substances is unpredictable, and it is best to start with markedly lower dosages than one would take for both substances individually. This combination may increase the neurotoxic effects of MDMA based on its similarity to LSD, which has been found to increase MDMA neurotoxicity.[18]
  • Alcohol - Alcohol can increase the disinhibiting and euphoric effects of 2C-B which lends to its use in recreational settings. It can be used in light doses to "take the edge off" a trip as well as dull its psychedelic effects in a fashion somewhat similar to benzodiazepines. However, this is not typically recommended due to alcohol’s ability to cause dehydration and nausea and physical fatigue which can negatively affect a trip if taken in moderate to high dosages. Heavy drinking is strongly discouraged as it can easily lead to black outs and unpredictable behavior.
  • Benzodiazepines - Benzodiazepines can, depending on the dosage, slightly to completely reduce the intensity of the cognitive, physical and visual effects of a 2C-B trip. They are very efficient at stopping "bad trips" at the cost of amnesia and reduced trip intensity. Caution is advised when acquiring them for this purpose due to their very high abuse and addiction potential.
  • Psychedelics - When used in combination with other psychedelics, each substance's physical, cognitive and visual effects intensify and synergize strongly. The synergy between those substances is unpredictable, and for this reason generally not advised. If choosing to combine psychedelics, it is recommended to start with significantly lower dosages than one would take for either substance individually.

Experience reports

Anecdotal reports which describe the effects of this compound within our experience index include:

Additional experience reports can be found here:

Toxicity and harm potential


This toxicity and harm potential section is a stub.

As such, it may contain incomplete or even dangerously wrong information. You can help by expanding or correcting it.
We also recommend that you conduct independent research and use harm reduction practices when using this substance.

The toxicity and long-term health effects of recreational 2C-B use have not been studied in any scientific context, and the exact toxic dose is unknown.

Anecdotal evidence suggests that there are no negative health effects attributed to simply trying it by itself at low to moderate doses or using it very sparingly (although nothing can be completely guaranteed).

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


2C-B at normal doses is unlikely to be neurotoxic.[19] Through rough extrapolations of data from rat cortical cultures, the IC50 of neuronal activity may result from a dose of at least a 330-650mg.[20] In other words, users should avoid a dose that large in order to avoid long term damage, but typical doses should be well within a safe range.

Cardiac risk

Users have reported experience hypertension, hyperthermia and tachycardia at higher doses.[21] As such, those with pre-existing heart conditions should avoid using 2C-B, and users monitor their temperature and heart-rate and respond accordingly. Heavy physical exertion while on 2C-B is discouraged.

Lethal dosage

There is no current data for the LD50 of 2C-B, but it is thought to be considerably higher than the active dose. Alexander Shulgin reported a 100 mg oral dose taken without apparent harm.[22]

Dependence and abuse potential

As with other serotonergic psychedelic, 2C-B is considered to be non-addictive with a low potential for abuse.

Tolerance to the effects of 2C-B are not built almost immediately after ingestion. There are many anecdotal reports of people ingesting this substance many days in a row with no immediate tolerance build up. 2C-B produces cross-tolerance with other serotonergic psychedelics, meaning that after the use of 2C-B all psychedelics will have a reduced effect.

Dangerous interactions

Although many psychoactive substances are reasonably safe to use on their own, they can quickly become dangerous or even life-threatening when combined with other substances. The list below includes some known dangerous combinations (although it cannot be guaranteed to include all of them). Independent research (e.g. Google, DuckDuckGo) should always be conducted to ensure that a combination of two or more substances is safe to consume. Some interactions listed have been sourced from TripSit.

  • Lithium - Lithium is commonly prescribed in the treatment of bipolar disorder. There is a large body of anecdotal evidence that suggests taking it with psychedelics significantly increases the risk of psychosis and seizures. As a result, this combination is strictly discouraged.
  • Cannabis - Cannabis has an unexpectedly strong and unpredictable synergy with the effects of psychedelics. Caution is advised with this combination as it can significantly increase the risk of adverse psychological reactions like anxiety, paranoia, panic attacks, and psychosis. Users are advised to start off with only a fraction of their normal cannabis dose and take long breaks between hits to avoid over intake.
  • Stimulants (Amphetamine, cocaine, methylphenidate, ...) - Stimulants affect many parts of the brain and alter dopaminergic function. Combined with psychedelics, stimulation can turn into severe anxiety, panic, thought loops, and paranoia. This interaction may result in an elevated risk of mania and psychosis.[citation needed]
  • Tramadol - Tramadol lowers the seizure threshold[23] and psychedelics may act as triggers for seizures in susceptible individuals.[citation needed]

Legal status

Internationally, 2C-B was added to the UN Convention on Psychotropic Substances as a Schedule II substance on March 20, 2001.[24]

  • Argentina: 2C-B is a Schedule I controlled substance.[25]
  • Australia: 2C-B is illegal to possess, produce and sell in Australia.[citation needed]
  • Austria: 2C-B is illegal to possess, produce and sell in Austria under the SMG (Suchtmittelgesetz Österreich).[citation needed]
  • Belgium: 2C-B is illegal to possess, produce and sell in Belgium.[citation needed]
  • Brazil: 2C-B is illegal to possess, produce and sell in Brazil as it is listed on Portaria SVS/MS nº 344.[26]
  • Canada: 2C-B is a Schedule III drug in Canada.[27]
  • Croatia: 2C-B is illegal to possess, produce and sell in Croatia as a result of it being a 2,5-dimethoxyphenylethanamine.[28]
  • Denmark: 2C-B is a List B controlled substance.[29]
  • Estonia: 2C-B is a Schedule I drug in Estonia.[citation needed]
  • European Union: 2C-B is a Schedule II drug in the EU.[citation needed]
  • Finland: Possession, production and sale of 2C-B is illegal in Finland.[citation needed]
  • Germany: 2C-B is controlled under Anlage I BtMG (Narcotics Act, Schedule I) as of January 31, 1993.[30][31] It is illegal to manufacture, possess, import, export, buy, sell, procure or dispense it without a license.[32]
  • Italy: 2C-B is a Schedule I (tabella I) drug in Italy[33]
  • Japan: Possession, production and sale is illegal.[citation needed]
  • Latvia: 2C-B is a Schedule I controlled substance.[34]
  • The Netherlands: Possession, production and sale is illegal.[citation needed]
  • Norway: 2C-B is a Schedule II drug.[citation needed]
  • Poland: 2C-B is a Schedule I drug.[citation needed]
  • Russia: Possession, production and sale is illegal.[citation needed]
  • Spain: 2C-B is a Category 2 drug.[citation needed]
  • Sweden: 2C-B is a Schedule I drug.[35]
  • Switzerland: 2C-B is a controlled substance specifically named under Verzeichnis D.[36]
  • Turkey: 2C-B is a classed as drug and is illegal to possess, produce, supply, or import.[37]
  • United Kingdom: 2C-B is a Class A drug in the United Kingdom as a result of the phenethylamine catch-all clause.[38]
  • United States: 2C-B is a Schedule I drug.[39]

See also

External links



  • González, D., Torrens, M., & Farré, M. (2015). Acute Effects of the Novel Psychoactive Drug 2C-B on Emotions. BioMed Research International, 2015. https://doi.org/10.1155/2015/643878
  • Papaseit, E., Farré, M., Pérez-Mañá, C., Torrens, M., Ventura, M., Pujadas, M., ... & González, D. (2018). Acute Pharmacological Effects of 2C-B in Humans: An Observational Study. Frontiers in Pharmacology, 9, 206. https://doi.org/10.3389/fphar.2018.00206


  1. Shulgin, A., & Shulgin, A. (1991). Erowid Online Books: "PIHKAL" - #20 2C-B. Retrieved Oct 26, 2017.
  2. Shulgin A. T., Carter M. F. Centrally active phenethylamines. Psychopharmacology Communications. 1975;1(1):93–98. PMID: 1223994
  3. Erowid 2-CB effects | http://www.erowid.org/chemicals/2cb/2cb_effects.shtml
  4. 2C-B (Nexus) Reappears on the Club Drug Scene | http://www.justice.gov/archive/ndic/pubs0/665/665p.pdf
  5. Phenethylamines I Have Known And Loved http://isomerdesign.com/PiHKAL/read.php?id=20
  6. Shulgin, A., & Shulgin, A. (1991). Erowid Online Books: "PIHKAL" - The Chemical Story. Retrieved April 14, 2017.
  7. https://www.scientificamerican.com/article/self-experimenter-chemist-explores-new-psychedelics/
  8. http://www.encyclopedia.com/science/applied-and-social-sciences-magazines/2c-b-nexus
  9. https://www.justice.gov/archive/ndic/pubs0/665/
  10. "2CB chosen over traditional entheogen's by South African healers". Tacethno.com. 2008-03-27. Retrieved May 15, 2012. 
  11. The Nexus Factor - An Introduction to 2C-B Erowid
  12. Ubulawu Nomathotholo Pack Photo by Erowid. © 2002 Erowid.org
  13. http://isomerdesign.com/PiHKAL/read.php?id=20
  14. Functional Selectivity of Hallucinogenic Phenethylamine and Phenylisopropylamine Derivatives at Human 5-Hydroxytryptamine (5-HT)2A and 5-HT2C Receptors | http://jpet.aspetjournals.org/content/321/3/1054
  15. http://onlinelibrary.wiley.com/doi/10.1038/sj.bjp.0705722/abstract;jsessionid=7F4731B4EF0AF36C37D0E3CA60319C4E.f03t04 | http://onlinelibrary.wiley.com/doi/10.1038/sj.bjp.0705722/abstract;jsessionid=7F4731B4EF0AF36C37D0E3CA60319C4E.f03t04
  16. http://jpet.aspetjournals.org/content/321/3/1054.full.pdf
  17. behavioral, neurochemical and pharmaco-EEG profiles of the psychedelic drug 4-bromo-2,5-dimethoxyphenethylamine (2C-B) in rats | http://link.springer.com/article/10.1007%2Fs00213-012-2797-7
  18. Armstrong, B. D., Paik, E., Chhith, S., Lelievre, V., Waschek, J. A., & Howard, S. G. (2004). Potentiation of (DL)‐3, 4‐methylenedioxymethamphetamine (MDMA)‐induced toxicity by the serotonin 2A receptior partial agonist d‐lysergic acid diethylamide (LSD), and the protection of same by the serotonin 2A/2C receptor antagonist MDL 11,939. Neuroscience Research Communications, 35(2), 83-95. https://doi.org/10.1002/nrc.20023
  19. Hondebrink, Laura, Anne Zwartsen, and Remco HS Westerink. "Effect fingerprinting of new psychoactive substances (NPS): What can we learn from in vitro data?." Pharmacology & therapeutics 182 (2018): 193-224. | https://www.sciencedirect.com/science/article/pii/S0163725817302723
  20. Zwartsen, Anne, Laura Hondebrink, and Remco HS Westerink. "Neurotoxicity screening of new psychoactive substances (NPS): Effects on neuronal activity in rat cortical cultures using microelectrode arrays (MEA)." Neurotoxicology 66 (2018): 87-97. | https://www.sciencedirect.com/science/article/pii/S0161813X1830086X?via%3Dihub#bib0050
  21. Papaseit, Esther et al. “Acute Pharmacological Effects of 2C-B in Humans: An Observational Study” Frontiers in pharmacology vol. 9 206. 13 Mar. 2018, doi:10.3389/fphar.2018.00206| https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5859368/
  22. "Shulgin, A (1991) PIHKAL" | http://www.erowid.org/library/books_online/pihkal/pihkal020.shtml
  23. Talaie, H.; Panahandeh, R.; Fayaznouri, M. R.; Asadi, Z.; Abdollahi, M. (2009). "Dose-independent occurrence of seizure with tramadol". Journal of Medical Toxicology. 5 (2): 63–67. doi:10.1007/BF03161089. ISSN 1556-9039. 
  24. "Inclusion of 4-bromo-2,5-dimethoxyphenethylamine (2C -B)" (in German). UNODC. Retrieved December 10, 2019. 
  25. "Decreto 299/2010 Actualización de la lista de estupefacientes y demás sustancias químicas que deberán ser incluidas en losalcances de la Ley Nº 23.737" (PDF) (in Spanish). Retrieved December 10, 2019. 
  26. http://portal.anvisa.gov.br/documents/10181/3115436/%281%29RDC_130_2016_.pdf/fc7ea407-3ff5-4fc1-bcfe-2f37504d28b7
  27. "CDSA Schedule II" | http://isomerdesign.com/Cdsa/schedule.php?schedule=3&section=ALL&structure=C
  28. "Popis droga, psihotropnih tvari i biljaka iz kojih se može dobiti droga te tvari koje se mogu uporabiti za izradu droga" | https://narodne-novine.nn.hr/clanci/sluzbeni/2016_01_10_258.html
  29. "Bekendtgørelse om euforiserende stoffer" (in Danish). Retrieved December 10, 2019. 
  30. "Vierte Verordnung zur Änderung betäubungsmittelrechtlicher Vorschriften" (in German). Bundesanzeiger Verlag. Retrieved December 10, 2019. 
  31. "Anlage I BtMG" (in German). Bundesministerium der Justiz und für Verbraucherschutz. Retrieved December 10, 2019. 
  32. "§ 29 BtMG" (in German). Bundesministerium der Justiz und für Verbraucherschutz. Retrieved December 10, 2019. 
  33. Italy drug schedule | http://www.salute.gov.it/medicinaliSostanze/paginaInternaMedicinaliSostanze.jsp?id=7&menu=strumenti
  34. Noteikumi par Latvijā kontrolējamajām narkotiskajām vielām, psihotropajām vielām un prekursoriem (2,5-Dimetoksifeniletānamīni) | http://likumi.lv/doc.php?id=121086
  35. http://www.lakemedelsverket.se/upload/lvfs/LVFS_2009-22.pdf
  36. "Verordnung des EDI über die Verzeichnisse der Betäubungsmittel, psychotropen Stoffe, Vorläuferstoffe und Hilfschemikalien" (in German). Bundeskanzlei [Federal Chancellery of Switzerland]. Retrieved January 1, 2020. 
  37. https://resmigazete.gov.tr/eskiler/2011/02/20110213-4.htm
  38. United Kingdom. (1977). Misuse of Drugs Act 1971 (S.I. 1977/1243). London: The Stationery Office Limited. Retrieved July 5, 2017, from http://www.legislation.gov.uk/uksi/1977/1243/made
  39. Schedules of Controlled Substances, 21 C.F.R. § 1308 (1995). Retrieved November 5, 2019, from https://www.deadiversion.usdoj.gov/21cfr/cfr/1308/1308_11.htm