4-MTA

Empathogen with very low chronic toxicity but high risk of acute harm due to mixed serotonin release and MAOI action. Reported to lack euphoria and rarely sold since being scheduled.

Also known as: Flatliners, 4-methylthioamfetamine, MTA, P-methylthioamfetamine, Para-methylthioamfetamine

Classification

Chemical: Amphetamine
Psychoactive: Entactogen
Psychoactive: Stimulant
Tag: Empathogen
Tag: Research-Chemical
Tag: Tentative

Effects

Stimulation
Teeth Grinding
Jaw Tension
Nausea
Tremor
Jerking
Anxiety
Agitation
Confusion
Talkativeness
Alertness Enhancement
Euphoria
Light Sensitivity
Dehydration
Increased Libido
Vibrating Vision
Open Eye Visuals
Disinhibition

Routes of Administration

Oral

Dosage

Heavy: 40+ mg (danger: markedly increased risk of serotonin syndrome and hyperthermia)
Light: 10-20 mg
Common: 20-30 mg
Strong: 30-40 mg (high risk)
Threshold: 5 mg

Duration

Onset: 0.75-2 h
Peak: 2-8 h
Offset: 8-20 h
After Effects: 20-44 h
Total Duration: 8-20 h

Harm Reduction

Check interactions before mixing substances, pay attention to dose spacing and hydration, and treat all dosage guidance as approximate rather than guaranteed safe.

Sources

Substance data is aggregated from the following public harm-reduction and reference sources.

Links

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