TMA-2

TMA-2, or 2,4,5-trimethoxyamphetamine, is a synthetic psychedelic amphetamine in the trimethoxyamphetamine family. It has methoxy groups at the 2-, 4- and 5-positions of the phenyl ring. TMA-2 is structurally distinct from the more familiar 3,4,5-trimethoxyamphetamine (TMA), and laboratory studies have confirmed strong activity at serotonin receptors associated with psychedelic effects.

Chemistry and relationship to other TMAs

TMA-2 is an alpha-methylated phenethylamine with a 2,4,5-trimethoxy substitution pattern. It is a positional isomer of other trimethoxyamphetamines, including TMA-6, which has methoxy groups at the 2-, 4- and 6-positions. The position of the methoxy groups is important: these isomers do not have interchangeable pharmacological profiles.

TMA-2 is also related to DOM and the wider DOx family, but its ring substitution pattern differs. DOM has two methoxy groups and a methyl group at the 4-position, rather than three methoxy groups.

Pharmacology

A receptor study examining TMA-2 and related 4-alkoxy-substituted amphetamines found moderate-to-high affinity at the 5-HT_2A receptor, with a preference over several other receptor targets. The researchers also measured activation at 5-HT_2A and 5-HT_2B, and found that small structural changes could alter receptor affinity and efficacy (Luethi and colleagues, 2020).

A mouse head-twitch study found that TMA-2 produced a 5-HT_2A-mediated behavioural response. Its structure–activity relationship differed from that of the 3,4,5-substituted TMA series, illustrating how the position of the methoxy groups can change psychedelic activity (Comparison of mescaline analogue effects in mice, 2019).

Subjective effects

The PsychonautWiki profile of TMA-2 and historical accounts describe psychedelic effects. With few controlled human observations, detailed descriptions of visual and emotional effects still rest largely on anecdotes.

Visual and cognitive effects

Reports associated with TMA-2 describe changes in visual perception, patterning, altered thought associations and shifts in mood. Introspection and changes in time perception are also mentioned. The available evidence does not establish how consistently these effects occur or how they compare with other trimethoxyamphetamines.

Physical effects

Historical and anecdotal accounts mention stimulation, nausea, muscle tension and changes in heart rate. Clinical information is too limited to establish how often these effects occur or how severe they are.

Toxicity and research limitations

There is no well-characterised clinical case series defining the acute toxicity of TMA-2. Receptor assays and animal behavioural studies support its psychedelic activity, but do not establish a human toxic range, pharmacokinetic profile or long-term safety.

Its structural relationship to other TMAs should not be used to assume identical effects. TMA-2 and TMA-6 are positional isomers with different methoxy substitution patterns, and each requires compound-specific evidence.

Related compounds

TMA-2 is related to TMA-6, DOM and other substituted amphetamine psychedelics. It is a positional isomer of TMA-6, not another name for the same compound.