2C-Se-TFM is a designer drug from the substituted phenethylamine family, which produces psychedelic-like effects in animals such as a head twitch response. It was first synthesised by Josh Hartsel and colleagues in 2024. It has a binding affinity (K<sub>i</sub>) of 3.2 nM at the serotonin receptor 5-HT<sub>2A</sub> and an EC<sub>50</sub> of 3.6 nM, acting as a full agonist. Aside from 2C-Se, it is the only psychedelic drug containing a selenium atom, as while other related analogues such as the ethyl compound 2C-Se-2 and the propyl derivative 2C-Se-7 have been proposed as theoretical compounds, neither is known to have been synthesised. It is a controlled substance in Canada under phenethylamine blanket-ban language.