RCT · 2026
2C-B compared head-to-head with MDMA and psilocybin in 24 healthy volunteers
- Original title
- Acute dose-dependent effects of 4-bromo-2,5-dimethoxyphenethylamine (2C-B) compared with 3,4-methylenedioxymethamphetamine (MDMA) and psilocybin in a double-blind, placebo-controlled study in healthy participants.
- Authors
- Arikci D, Borgulya J, Straumann I, et al.
- Journal
- Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology, 2026
- Molecules
- 2C-B, MDMA, Psilocybin
- Conditions
- Healthy volunteers
- Participants
- 24
- Evidence grade
- Moderate
- Source
- Read the original paper
The question
How do the acute effects of the psychedelic 2C-B compare with standard doses of MDMA and psilocybin in healthy people?
What they did
Twenty-four healthy adults (12 women, 12 men) each received, on separate occasions, 2C-B at 10, 20 and 30 mg, 125 mg of MDMA, 25 mg of psilocybin, and a placebo. Neither participants nor researchers knew which substance was given on a given day (double-blind, crossover design). The researchers tracked subjective experience, heart and blood pressure effects, side effects, empathy tasks, blood oxytocin levels, and how the drug was processed by the body over 9 hours.
What they found
2C-B produced stronger effects as the dose rose. At 30 mg, its overall “any drug effect” rating was comparable to MDMA but lower than psilocybin. Only psilocybin produced more “bad drug effects” and “anxiety” than placebo. The 30 mg dose of 2C-B altered consciousness in a psychedelic way and raised emotional empathy much like MDMA, and its effects lasted on average 4.9 hours, similar to MDMA (4.8 hours) and shorter than psilocybin (6.1 hours). MDMA raised heart and circulation measures the most, then psilocybin, then 2C-B, and only MDMA increased blood oxytocin and neurophysin I. 2C-B left the blood quickly, with a half-life of about 1.3 hours.
The fine print
This was a small study of 24 healthy volunteers in a controlled laboratory setting, so results may not carry over to people with depression, PTSD or other conditions. Only one dose each of MDMA and psilocybin was tested, so the comparisons apply to those dose levels only. Effects were measured on a single day per condition with no longer-term follow-up, and blinding is difficult when drug effects are obvious. This summary is based on the abstract alone.
What it means
In healthy volunteers, 2C-B at 30 mg produced effects resembling both MDMA and psilocybin, with shorter duration, less cardiovascular stimulation than MDMA and less anxiety than psilocybin; the findings are a starting point for choosing doses in future research, not evidence that it treats anything.
Evidence grade: Moderate. A double-blind, placebo-controlled crossover randomized trial, but with only 24 healthy volunteers, single sessions per condition and no clinical outcomes.
This summary is based on the study’s published abstract.