The hallucinogen 25B-NBOMe, which binds strongly to serotonin receptors, increased dopamine, serotonin, and glutamate release in the rat frontal cortex, striatum, and nucleus accumbens. It induced hallucinogenic activity, impaired short-term memory as measured by the novel object recognition test, and reduced locomotor activity in the open field test. In the light/dark box, rats spent more time in the dark zone, suggesting an anxiogenic effect. Scopolamine blocked the memory impairment. Unlike MDMA, 25B-NBOMe showed a subtle genotoxic effect in the comet assay. The changes in neurotransmitter levels may stem from its affinity for the 5-HT2A receptor.
Repeated daily injections of the hallucinogenic drug 25I-NBOMe for seven days in rats reduced the brain's release of dopamine, serotonin, and glutamate in the frontal cortex and weakened hallucinogenic behavior compared to a single dose. In contrast, dopamine and serotonin release increased in the striatum and nucleus accumbens, and acetylcholine release rose across all brain regions. Chronic treatment also reduced motor activity, impaired short-term memory, and induced anxiety. These findings indicate that repeated use of 25I-NBOMe produces tolerance to its hallucinogenic effects while altering multiple neurotransmitter systems, with complex effects on memory, movement, and anxiety.