In brief
- A double-blind crossover trial from the University of Basel compared three doses of 2C-B with 125 mg of MDMA, 25 mg of psilocybin, and a placebo in 24 healthy volunteers.
- At 30 mg, 2C-B produced an overall effect comparable to MDMA, combining perceptual alterations with increased emotional empathy, lasting an average of five hours.
- At the tested doses, MDMA produced the most cardiovascular stimulation; only psilocybin increased anxiety and unpleasant-effect ratings versus placebo. This is not a general safety ranking.
A Basel team compared acute effects of 2C-B, MDMA, psilocybin and placebo in 24 healthy adults. The study was published in Neuropsychopharmacology.
A crossover design for acute effects
Twenty-four healthy participants—twelve women and twelve men—took part in a randomized, double-blind, placebo-controlled crossover trial where every participant went through each experimental condition. The researchers tested three doses of 2C-B—10, 20, and 30 mg—against 125 mg of MDMA and 25 mg of psilocybin. A crossover design controls some between-person variability without eliminating expectations, order effects or the limits of a small sample.
An Intermediate Profile
The 30 mg dose produced an “overall effect” comparable to that of MDMA and lower than psilocybin’s. Looking closer, 2C-B acted as a true hybrid: it induced psychedelic perceptual shifts alongside an increase in emotional empathy akin to MDMA. The mean duration of subjective effects was approximately 4.9 hours, virtually identical to MDMA’s and shorter than psilocybin’s 6.1 hours. Its pharmacokinetics scaled linearly with dose, showing a plasma half-life of roughly 1.3 hours.
The safety and qualitative differences proved just as illuminating. MDMA induced the highest cardiovascular stimulation and was the sole compound to elevate oxytocin levels. Only psilocybin increased anxiety and unpleasant-effect ratings versus placebo at the studied doses; this does not mean every participant felt anxiety or that the other treatments lack risks. At those doses, 2C-B showed less cardiovascular stimulation than MDMA and lower distressing-effect ratings than psilocybin, without constituting a general safety ranking. The authors conclude that it blends entactogenic and psychedelic qualities, occupying an intermediate space between the two.
What This Means
The trial characterizes acute effects at specific doses and can inform further pharmacology questions. It does not establish a consumption regimen, a safe dose or therapeutic equivalence outside those conditions. More context in our guide to MDMA and empathogens.
The small healthy sample and clinical supervision limit generalization. The design cannot estimate rare harms, repeated use, mixtures or responses in people with illnesses. Composition testing alone does not eliminate risks. Our harm reduction guide provides general context rather than turning this trial into a dose recommendation.
Source
- Arikci D, Borgulya J, Straumann I et al. Acute dose-dependent effects of 4-bromo-2,5-dimethoxyphenethylamine (2C-B) compared with MDMA and psilocybin in a double-blind, placebo-controlled study in healthy participants. Neuropsychopharmacology 51(8):1511-1518, July 2026. DOI 10.1038/s41386-026-02428-9.
Educational content written from a harm reduction perspective and with respect for individual freedom. It is not a substitute for advice from a healthcare professional and is not intended to encourage or condemn any drug use.
