2,5-Dimethoxy-4-iodoamphetamine (DOI) is a psychedelic drug and a substituted amphetamine. Unlike many other substituted amphetamines, however, it is not primarily a stimulant. DOI’s effects have been compared to LSD, although there are differences that experienced users can distinguish. Besides the longer duration, the trip tends to be more energetic than an LSD trip, with more body load and a different subjective visual experience. The after effects include residual stimulation and difficulty sleeping, which, depending on the dose, may persist for days. While rare, it is sometimes sold as a substitute for LSD, or even sold falsely as LSD, which may be dangerous because DOI does not have the same established safety profile as LSD.
DOI is not scheduled in the United States, but it is likely that DOI would be considered an analog (of DOB), in which case, sales or possession could be prosecuted under the Federal Analogue Act. DOI is regularly used in animal and in vitro research. Scheduling DOI could cause problems for medical researchers.