2C-B Induces Psychedelic and Empathogenic Effects Similar to MDMA and Psilocybin in Healthy Subjects

4-bromo-2,5-dimethoxyphenethylamine (2C-B) is a psychoactive substance with a unique pharmacological profile, reportedly combining effects of both empathogens like 3,4-methylenedioxymethamphetamine (MDMA) and classic psychedelics such as psilocybin. While MDMA primarily acts by releasing serotonin (5-HT) via the serotonin transporter (SERT), and psilocybin functions as a direct agonist at 5-HT2A receptors, 2C-B interacts with both the 5-HT2A receptor and SERT. This dual mechanism suggests a mixed effects profile, yet robust scientific studies comparing its acute effects to these well-known substances have been notably lacking. Given the increasing psychiatric research interest in the therapeutic potential of MDMA for posttraumatic stress disorder and psilocybin for depressive disorders, understanding mixed empathogenic-psychedelic substances like 2C-B is crucial for exploring novel therapeutic avenues.

This study employed a double-blind, placebo-controlled design to investigate the acute dose-dependent effects of 4-bromo-2,5-dimethoxyphenethylamine (2C-B) in healthy participants. The intervention involved administering 30 mg 2C-B, alongside active comparators MDMA and psilocybin, and a placebo arm. Participants received single oral doses of each substance in a randomized order. The primary endpoints included subjective alterations of state of consciousness, emotional empathy, and subjective effect duration. Cardiovascular parameters were also monitored to assess physiological responses across the different compounds. The study aimed to characterize 2C-B's profile against established empathogens and psychedelics.

The administration of 30 mg 2C-B significantly induced psychedelic-type alterations of state of consciousness, a key finding that aligns its effects with classic psychedelics. Furthermore, this dose of 2C-B notably increased emotional empathy, demonstrating a profile similar to that observed with MDMA.

The average subjective effect duration for 30 mg 2C-B was 4.9 hours, which was statistically similar to the 4.8 hours reported for MDMA. In contrast, the subjective effect duration for psilocybin was significantly longer, averaging 6.1 hours. While 2C-B and psilocybin elicited psychedelic effects, and 2C-B and MDMA shared empathogenic properties, MDMA produced the highest cardiovascular effects among the tested substances. This suggests a differentiated physiological safety profile, with 2C-B potentially offering a more balanced acute experience regarding both psychological effects and cardiovascular load compared to MDMA, while having a more manageable duration than psilocybin for potential therapeutic applications.