2C-B is a psychedelic drug similar to mescaline. It was first synthesised by Alex Shulgin in 1974 and is considered to have effects that lie somewhere between that of LSD and MDMA.2

2C-B commonly comes in the form of a pill or a powder (pills are usually white but can be any colour) and is often sold as ecstasy in the underground rave scene, despite being a very distinct substance with markedly different effects at higher doses.

At lower doses, the experience can in fact be similar to ecstasy, with feelings of empathy, euphoria, and a greater appreciation for music. Yet, at higher doses, closed and even open-eye visuals can be present as well as spiritual insights and a “softening” of the ego.3


Set and setting


Dose carefully


Avoid mixing


Here are the most common effects, not everyone necessarily experiences all of them every time they consume the drug and other effects not listed might be felt. The likelihood of experiencing negative effects is far greater at high doses.

The effects are (from positive to negative):

    • Euphoria and laughter
    • Increased libido
    • Enhanced sensory awareness (sound, touch, vision) with closed and open eye visuals and synaesthesia6
    • Empathic feelings7
    • Feelings of great insight or spirituality
    • Increase in body temperature8
    • Increased energy
    • A change in the perception of time
    • Insomnia
    • Nausea and vomiting*
    • Headaches (most likely to occur on the comedown)
    • Excessive sweating
    • Dizziness
    • Anxiety and paranoia*
    • Jitters*

* Much more common among first-time users

Dose and Onset

How? How much? When? For how long?

Read our section on dosing and tolerance in ME for more information.

As with any drug, the correct dose for you depends on factors such as weight, gender, metabolism, whether you have taken the drug recently or not, amongst many others.

How you take it matters...

The least harmful way to consume 2C-B is orally: either via ingestion, which can mean swallowing a pill, “bombing” (wrapping 2C-B powder in cigarette paper and swallowing it)10 or “gumming”, where the drug is rubbed into the gums with a fingertip.

Nasal intake has been reported to be extremely painful and is best avoided11. Due to this we recommend avoiding this method of consumption. It is worth noting that taking the powder through the nose results in a much faster onset and a shorter total duration12. There are reports of people smoking 2C-B, however the responses vary widely: some experiencing negative effects, minimal effects or none at all. It also makes it easier to take too much.


How much?

  • Threshold - 2-5 mg
  • Light - 5-15 mg
  • Common - 15-25 mg
  • Strong - 25-50 mg (taking any amount greater than 50 mg puts the user at serious risk of adverse effects.)13

Source: erowid.org

When do the effects kick in and for how long?

The main effects will likely last between 4 and 8 hours depending on the dose, the individual and the contents of their stomach. If taken orally without being on an empty stomach the onset can be delayed while the effects are slightly prolonged but also slightly diminished.


  • Onset: 45-75 minutes
  • Come-up: 15-30 minutes
  • Plateau: 2-4 hours
  • Come-down: 1-2 hours
  • After effects: 2-4 hours


  • Onset: 1-10 minutes
  • Duration: 2-4 hours
  • Come-down: 1-2 hours
  • After-effects: 2-4 hours

Source: erowid.org


+ ? =

dangerous to synergy bar


Click one of the drugs below and see how it mixes with .


Source: tripsit.me

Harm reduction

There are certain precautions you should take before doing 2C-B. The advice below helps you to be physically and mentally prepared before doing it. Furthermore, we want you to be safe, and just in case you have a bad experience or some of the unwanted side effects associated with 2C-B, we have also provided information on how to take care of yourself when you are in full swing. Finally, there are those uncomfortable or undesirable effects after the high have worn out, we will provide you with some practical tips on how to have a better calm down and help you to reduce the harm done to your body and brain. 

Head over to our ME section if you would like to know more about harm reduction.





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Dependence to 2C-B is unlikely but by no means impossible, but taking it over successive days will greatly reduce its effects due to an increased tolerance, known as tachyphylaxis21. It is therefore self-limiting, as there is little reward for taking the drug continuously.

The Law



  • USA: Illegal, Schedule I section D 1995
  • Canada: Schedule III
  • Mexico:Illegal.

Asia and Australia

  • Australia: Illegal
  • New Zealand: Illegal
  • Singapore: Illegal
  • Hong Kong: Illegal
  • Israel: Illegal


  • South Africa: Illegal

More information, references, useful links...

More information



Can I take 2C-B if I am on SSRIs?24

In theory, this is possible. However, a larger dose may  be required and estimating this increase in dose can be risky and difficult.

Can I take 2C-B if I am on MAOIs?

Although this combination is unlikely to cause a fatality as it might with MDMA, it is best err on the side of caution and avoid 2C-B if you take MAOIs.25

What about Tricyclics?

Although there is no clear interaction between the two drugs, bear in mind that tricyclic antidepressants can potentiate the effects of benzodiazepines.

Can I take 2C-B if I have a heart condition?

This greatly depends on exactly what your diagnosis is. However, you can minimise the risks by not doing excessive physical activity such as dancing while on the drug.


  1. "2C-B Street Names" (PDF). February 1, 2011.
  2. "2C-B (Nexus) Reappears on the Club Drug Scene" (PDF). National Drug Intelligence Center. Department of Justice. May 2001.
  3. Pharmacological Studies of Some Psychoactive Phenylalkylamines-Entactogens, Hallucinogens, and Anorectics, Nicholas Cozzi.
  4. Caudevilla-Galligo, F.; Riba, J.; Ventura, M.; González, D.; Farré, M.; Barbanoj, M. J.; Bouso, J. C. (2012). "4-Bromo-2,5-dimethoxyphenethylamine (2C-B): Presence in the recreational drug market in Spain, pattern of use and subjective effects". Journal of Psychopharmacology.
  5. "Erowid 2C-B Vault: Basics". Erowid
  6. https://en.wikipedia.org/wiki/Synesthesia
  7. Gonzalez D, Torrens M, Acute Effects of the Novel Psychoactive Drug 2C-B on Emotions.
  8. Carmo, H.; Hengstler, J. G.; De Boer, D. D.; et al. (2005). "Metabolic pathways of 4-bromo-2,5-dimethoxyphenethylamine (2C-B): Analysis of phase I metabolism with hepatocytes of six species including human". Toxicology. 206 (1): 75–89. doi:10.1016/j.tox.2004.07.004. PMID 15590110
  9. http://drugs.tripsit.me/2c-b
  10. http://www.synchronium.net/2010/05/06/how-to-make-a-bomb/
  11. https://erowid.org/chemicals/2cb/2cb_faq.shtml
  12. "Erowid 2C-B Vault: Effects". Erowid. Retrieved 2018-01-02.
  13. De Boer, D.; Gijzels, M. J.; Bosman, I. J.; Maes, R. A. A. (1999). "More Data About the New Psychoactive Drug 2C-B". Journal of Analytical Toxicology.
  14. "Erowid 2C-B Vault: Basics". Erowid. 2011-02-20
  15. Kanamori, Tatsuyuki, et al. In vivo metabolism of 4-bromo-2, 5-dimethoxyphenethylamine (2C-B) in the rat: identification of urinary metabolites. Journal of analytical toxicology 26.2 (2002): 61-66.
  16. https://www.webmd.com/depression/guide/serotonin-syndrome-causes-symptoms-treatments#1
  17. Boyer, Edward W.; Shannon, Michael (2005). "The Serotonin Syndrome". New England Journal of Medicine. 352 (11): 1112–20
  18. https://www.reddit.com/r/Drugs/comments/2sxvbd/best_benzo_for_a_come_down/
  19. GOV.UK, Controlled Substances, Retrieved from https://www.gov.uk/government/publications/controlled-drugs-list--2/list-of-most-commonly-encountered-drugs-currently-controlled-under-the-misuse-of-drugs-legislation, 01/02/2018
  20. Misuse of Drugs Act 1971. Retrieved from https://www.legislation.gov.uk/ukpga/1971/38/contents
  21. http://www.drugsand.me/me.html#tolerance
  22. "List of psychotropic substances under international control"(PDF). Archived from the original (PDF) on 2 March 2007.
  23. UK Government, most commonly encountered illegal drugs, https://www.gov.uk/government/publications/controlled-drugs-list--2/list-of-most-commonly-encountered-drugs-currently-controlled-under-the-misuse-of-drugs-legislation
  24. "Clinical Pharmacology of SSRI's: Why Are CYP Enzymes Important When Considering SSRIs?
  25. Tatsumi M, Groshan K, Blakely RD, Richelson E (1997). "Pharmacological profile of antidepressants and related compounds at human monoamine transporters". Eur J Pharmacol.

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