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The molecular structure of 2C-B
  • 2C-B refers to the synthetic psychoactive substance 2,5-dimethoxy-4-bromophenethylamine. 2C-B is a phenylethylamine derivative and has a similar structure to mescaline. It is described as a psychedelic with some stimulant-like properties, with anecdotal reports drawing similarities between LSD and MDMA.

    2C-B was synthesised by Alexander Shulgin in 1974 and his findings were reported in his 1991 book entitled PiHKAL. Following its discovery, there was some reported use of 2C-B by psychotherapists in the 1970s, which was followed by a breakthrough of use into the recreational drug scene in the 70s and 80s. 2C-B had a short-lived legitimate history and was marketed as an aphrodisiac in smart shops in America and the Netherlands, before being classified as illegal in several countries, including the UK, in the 90s. Currently, 2C-B (and other 2C drugs) are Class A, Schedule 1 drugs in the UK. This means they are illegal to possess, supply and produce. In recent years, 2C-B has increased in popularity in sales over the darknet, and is popular in the rave and festival scene.

  • 2C-B is typically found as a powder (often white crystals), pill or in a capsule. These are typically taken orally and the standard oral dose is between 15-25 mg.

    2C-B can also be insufflated (snorted), although this carries increased risk because the dosage required to achieve active effects is much lower than an oral dose. There are anecdotal reports of pain when snorting 2C-B.\

    We strongly advise against nasal insufflation of 2C-B

  • There is still very limited research into the mechanisms of action of 2C-B in the human brain and body. However, it is suggested that 5-HT2 and α-adrenergic receptors are involved. The 5-HT2A receptor is associated with classical psychedelics, including LSD and psilocybin, whereby the drug binds and act as agonists. There is conflicting evidence concerning the mechanism of action of 2C-B, as some research suggests that 2C-B acts as a partial agonist at the 5-HT2A receptor, whilst other research suggests that 2C-B acts as an antagonist at the 5-HT2A receptor. It has also been suggested that the 5-HT2C receptor may be involved in the response activated and that the α1-adrenergic receptor is responsible for the stimulant effects.

  • The onset time of 2C-B is typically between 45-75 minutes after oral consumption. A ‘come up’ period with a duration of 15-30 minutes is commonly described and can include feelings of anticipation and anxiety, as well as bodily sensations including tingling and pins and needles.

    Although there are anecdotal reports of the effects of 2C-B, recent observational studies have provided valuable insight into the emotional and pharmacological effects of 2C-B. The effects of 2C-B are heavily dose-dependent and typically include:

    • Enhanced mood and feelings of euphoria

    • Laughter

    • Visual and auditory alterations and hallucinations

    • Enhanced energy

    • Sexual arousal/enhanced libido

    • Nausea, vomiting and diarrhoea

  • After the synthesis of 2C-B by Alexander Shulgin in 1974, there were reports that he recommended its use in therapy to a limited number of psychotherapists due to the empathogenic effects of 2C-B.

    There is very limited clinical research into the medical uses of 2CB, however an observational study showed that 2C-B acts as an entactogenic drug. Entactogens have effects which include emotional openness, oneness and introspection. MDMA is also described as an entactogen and this property is attributed to its potential use as a tool in psychotherapy for several psychiatric conditions, including PTSD. Therefore, it has been suggested by some that 2C-B may pose the therapeutic benefit that Alexander Shulgin had claimed.

  • 2C-B induces a psychedelic experience including alterations to mood, as well as visual and auditory hallucinations. The nature of a 2C-B trip can be emotionally challenging for some people, inducing states of anxiety and paranoia. Similar to all psychedelics, the psychological risks can be minimised by ‘set and setting’, ensuring that both your mind-set is stable and well prepared, and that the environment is comfortable and safe.

    Anecdotal reports suggest that recreational doses of 2C-B are associated with low toxicity and are physiologically well tolerated. However, there is a lack of scientific studies on the toxicity and long-term effects of 2C-B. A recent observational study investigated the immediate pharmacological effects of 2CB, demonstrating increased heart rate and blood pressure after 2CB consumption. Therefore, 2C-B may be dangerous for those with heart conditions.

    The dosage of 2C-B is in the milligram region and the effects are highly dose dependent. There is a very steep dose response curve, which means that small changes to the dose that may be undetectable by eye could have drastic effects on the 2C-B experience. Alexander Shulgin states in PiHKAL that “over the 12 to 24 milligram range, every 2 milligrams can make a profound increase or change of response.” Therefore, it is critical that doses are measured accurately.

    Snorting of 2C-B is highly inadvisable and there are anecdotal reports of pain associated with insufflation. Extra caution is required with snorting as the dose required is much smaller than an oral dose and the onset is very rapid, often within minutes.

    2C-B can be tested using the Marquis Reagent (NIK® test A) and will produce a yellow/green colour. However, extra caution is needed as 2C-I (another 2C drug with different effects) will also give a yellow/green colour using the Marquis Reagent (NIK® test A). There are other drug testing kits available that can be used for further clarification of substances, but it is important to appreciate the limitations in determining the differences between the 2C series of drugs which includes 2C-B, 2C-D, 2C-E, 2C-I, and 2C-P.

    Read more about 2C-B harm reduction here.

  • Similar to other psychedelic drugs, a history of mental health illness (such as schizophrenia, psychosis or bipolar disorder) may increase the likelihood of an unpleasant experience (‘bad trip’) and there is the risk 2C-B may exacerbate these conditions. However, there is still a very limited understanding of the dangers associated with the use of psychedelics in those with pre-existing mental health conditions. There has been a report of psychosis after 2C-B, however it is important to state that the purity of the 2C-B was not confirmed in this case.

    2C-B increases heart rate and blood pressure. These effects could be more dangerous for those with a history of heart conditions or high blood pressure. Some have suggested that 2C-B may present more risks for those with diabetes or epilepsy.

    It is important to understand the metabolism of 2C-B by the body and the potential implications this may have. 2C-B is metabolised by enzymes called monoamine oxidases (MAOs) A and B, and therefore this could pose a risk for those on Monoamine Oxidase Inhibitors (MAOIs).

    Prescription drugs with an associated risk:

    • MAOIs (some antidepressants)

    • Tramadol

    • Antipsychotics

    • Antihypertensives

    • Central nervous system depressants

    • Vasodilators

  • 2C-B should not be consumed with alcohol or other drugs. An understanding of the effects and mechanisms of 2C-B can provide insight into the risks associated with mixing 2C-B with other drugs.

    Key drug combinations to avoid are listed below:

    • 2C-B should not be mixed with tramadol due to the increased risk of seizure

    • 2C-B should not be mixed with ayahuasca or ‘changa’ as they both contain MAOIs

    • 2C-B should not be mixed with other stimulants including cocaine and amphetamines

    • 2C-B should not be mixed with cannabis

    • 2C-B should not be mixed with other psychedelics as this carries the risk of making the trip more intense

    • 2C-B should not be mixed with any recreationally used prescription drugs that are known to potentially interact with 2C-B.


    This includes all those listed here.

  • 2C-B addiction is unlikely because 2C-B is considered to have a low potential for addiction, similar to other psychedelic drugs.

  • 2C-B produces a psychedelic experience with some stimulant-like properties. Informed harm reduction advice can help to mitigate some of the associated risks.

    Being educated and prepared

    It is important that you fully educate yourself on the health risks and drug interactions associated with 2C-B, and ensure that an accurate and suitable dose is consumed. 2C-B has some stimulant properties and therefore it is important to remain hydrated, especially if dancing.

    Set and setting

    ‘Set’ refers to a person’s mind-set including their mood, thoughts and expectations. This can have a significant effect on the experience of the trip and therefore it is advised that 2C-B is only consumed when a person is in a positive and stable state of mind. ‘Setting’ refers to the environment and social situation in which the drug is consumed. Although some consider 2C-B a milder psychedelic, it is advisable that it is consumed in a safe and familiar environment.


    The presence of a sober sitter is recommended for those with limited experience of psychedelic drugs. The sitter can provide reassurance and support during and after the trip.

  • Other 2C drugs

    2C-B is part of the 2C family of psychedelic phenethylamines, many of which were originally synthesised by Alexander Shulgin. Other popular 2C drugs include 2C-D, 2C-E, 2C-I and 2C-P. However, the effects of each 2C drug will vary and education of the differences is recommended before consumption of other 2C drugs.

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