Locomotor and discriminative stimulus effects of NBOH hallucinogens in rodents.

Four novel synthetic hallucinogens structurally similar to 25X-NBOMe compounds—25B-NBOH, 25C-NBOH, 25E-NBOH, and 25I-NBOH—were tested in mice and rats. All four decreased spontaneous locomotor activity in mice, with effects similar in magnitude and potency to the hallucinogen DOM but less potent than 25X-NBOMe compounds. In rats trained to discriminate DOM, 25B-NBOH, 25C-NBOH, and 25E-NBOH fully substituted for DOM, indicating they produce similar psychoactive effects, while 25I-NBOH failed to fully substitute even at doses that suppressed responding. The findings suggest three of the four compounds are likely to be used recreationally as hallucinogens, whereas 25I-NBOH may have lower abuse liability.

Study at a glance

Abstract

Despite the efforts of the Drug Enforcement Administration to safeguard the public from hazardous analogs of synthetic hallucinogens, these compounds have increasingly been observed in the illicit drug market. Four novel compounds were found to be similar in structure to the previously described 25X-NBOMe synthetic hallucinogens. These four compounds, 25B-NBOH, 25C-NBOH, 25E-NBOH, and 25I-NBOH were evaluated for their ability to modify spontaneous locomotor activity in mice to obtain dose range and time-course information and were then tested for discriminative stimulus effects similar to the prototypical hallucinogen (-)-2,5-dimethoxy-4-methylamphetamine (DOM). All four test compounds decreased locomotor activity. The locomotor depressant effects were similar in magnitude and potency to DOM, but less potent than the 25X-NBOMe compounds in previous reports. 25B-NBOH, 25C-NBOH, and 25E-NBOH fully substituted (≥80%) in DOM-trained rats, whereas 25I-NBOH failed to fully substitute for DOM even at doses that suppressed responding. The discriminative stimulus effects were more potent than those of DOM and the 25X-NBOMe compounds. These findings suggest that three of the four test compounds are most likely to be used as recreational hallucinogens in a similar manner to DOM and the 25X-NBOMe compounds, whereas 25I-NBOH may be less liable to illicit use.