α-Alkyltryptamines are a group of substituted tryptamines which possess an alkyl group, such as a methyl or ethyl group, attached at the alpha carbon, and in most cases no substitution on the amine nitrogen. α-Alkylation of tryptamine makes it much more metabolically stable and resistant to degradation by monoamine oxidase, resulting in increased potency and greatly lengthened half-life. This is analogous to α-methylation of phenethylamine into amphetamine.
Many α-alkyltryptamines are drugs, acting as monoamine releasing agents, non-selective serotonin receptor agonists, and/or monoamine oxidase inhibitors, and produce psychostimulant, entactogen, and/or psychedelic effects. The most well-known of these agents are α-methyltryptamine (αMT) and α-ethyltryptamine (αET), both of which were used clinically as antidepressants for a brief period of time in the past and are abused as recreational drugs. In accordance with its action as a dual releasing agent of serotonin and dopamine, αET has been found to produce serotonergic neurotoxicity similarly to amphetamines like MDMA and PCA, and the same is also likely to hold true for other serotonin and dopamine-releasing α-alkyltryptamines such as αMT, 5-MeO-αMT, and various others.