6-Fluoro-DET

6-Fluoro-DET (6F-DET, 6-fluoro-N,N-diethyltryptamine) is a substituted tryptamine derivative related to drugs such as DET and 5-fluoro-DET. It acts as a partial agonist at the 5-HT_2A receptor, but while it produces similar physiological effects to psychedelic drugs, it does not appear to produce psychedelic effects itself even at high doses. Relatedly, 6-F-DET does not substituted for LSD in drug discrimination tests and does not produce the head-twitch response in rodents. For the preceding reasons, it saw some use as an active placebo in early clinical trials of psychedelic drugs but was regarded as having little use otherwise, though more recent research into compounds such as AL-34662, TBG and zalsupindole has shown that these kind of non-psychedelic 5-HT_2A agonists can have various useful applications.

A hypothesis for the lack of head-twitch response in mice and hallucinogenic effects in humans is that 6-F-DET acts as a 5-HT_2A receptor partial agonist of the Gq signaling pathway. This hypothesis explains the lack of hallucinogenic effects of other 5-HT_2A receptor ligands, which are also weak Gq agonists and below the efficacy threshold found to induce psychedelic effects, like 25N-N1-Nap, 2-Br-LSD, lisuride, tabernanthalog, and 6-MeO-DMT.