Alternative names
4-MTA
Current Scheduling Status
None
Year(s) and type of review / ECDD meetings
Drug Class
Recommendation (from TRS)
Substance identification
4-Methylthioamphetamine (CAS 14116-06-4) is also known as 4-MTA. Other names include "MK", α-methyl-4-methylthiophenethylamine,
"MTA", p-methylthioamphetamine (p-MTA), "S5", "Flatliner" and "The One and Only Dominator". 4-MTA has one chiral centre and can exist as two enantiomers and a racemate. To date, only the racemic mixture has been reported to have been synthesized.
WHO review history
4-MTA has not been pre-reviewed by the Committee. However, the Committee decided to undertake a critical review of 4-MTA because it met the requirements for critical review specified in section 4.1, item (4).
Similarity to known substances and effects on the CNS
4-MTA is structurally similar to 4-methoxyamphetamine and is both a potent serotonin-releasing agent and a reversible inhibitor of monoamine oxidase A (MAO-A). Pharmacologically, it is similar to tenamfetamine (methylenedioxyamphetamine or MDA) and MDMA; studies suggest that 4-MTA is six times as potent as these substances in inhibiting 5-HT uptake.
Dependence potential
Drug discrimination studies in rats suggest that 4-MTA produces discriminative stimulus effects similar to MDMA. However, 4-MTA did not substitute for amphetamines, LSD or phencyclidine. Reports from the United Kingdom indicate that 4-MTA, like MDMA, is abused for its stimulant/euphoric effects (a "rush").
Actual abuse and or/evidence of likelihood of abuse
4-MTA is abused mainly in Europe, where it appears to be part of the dance music culture. However, it is likely that its use is less widespread than it otherwise might be because of perceptions among users that the drug is stronger and more harmful than other "club drugs", such as MDMA. Abuse of 4-MTA has resulted in a number of fatalities and hospital admissions. It appears that toxic effects can be produced directly from the drug, and that the presence of other drugs or alcohol mav exacerbate such effects.
Therapeutic usefulness
4-MTA has no recognized therapeutic use.
Recommendation
4-MTA is chemically and pharmacologically similar to 4-methoxyamphetamine, MDA and MDMA. It is a relatively new synthetic drug, and was seized for the first time in 1997. Although evidence of its actual abuse is available only in several European countries, recent seizures, including those of large quantities reported from a wider range of countries, suggest that trafficking and abuse of 4-MTA have become more widespread. On the basis of this information and its similarity to known MDA-type drugs, as well as drug discrimination studies in animals, it is estimated that 4-MTA is likely to be abused so as to constitute a public health and social problem, warranting its placement under international control. Taking into consideration that 4+-MTA has no recognized therapeutic use and that it has caused a number of fatalities, the Committee concluded that abuse of 4-MTA represents an especially serious risk to public health. The Committee therefore recommended that 4-MTA be placed in Schedule I of the 1971 Convention.
4-Methylthioamphetamine (CAS 14116-06-4) is also known as 4-MTA. Other names include "MK", α-methyl-4-methylthiophenethylamine,
"MTA", p-methylthioamphetamine (p-MTA), "S5", "Flatliner" and "The One and Only Dominator". 4-MTA has one chiral centre and can exist as two enantiomers and a racemate. To date, only the racemic mixture has been reported to have been synthesized.
WHO review history
4-MTA has not been pre-reviewed by the Committee. However, the Committee decided to undertake a critical review of 4-MTA because it met the requirements for critical review specified in section 4.1, item (4).
Similarity to known substances and effects on the CNS
4-MTA is structurally similar to 4-methoxyamphetamine and is both a potent serotonin-releasing agent and a reversible inhibitor of monoamine oxidase A (MAO-A). Pharmacologically, it is similar to tenamfetamine (methylenedioxyamphetamine or MDA) and MDMA; studies suggest that 4-MTA is six times as potent as these substances in inhibiting 5-HT uptake.
Dependence potential
Drug discrimination studies in rats suggest that 4-MTA produces discriminative stimulus effects similar to MDMA. However, 4-MTA did not substitute for amphetamines, LSD or phencyclidine. Reports from the United Kingdom indicate that 4-MTA, like MDMA, is abused for its stimulant/euphoric effects (a "rush").
Actual abuse and or/evidence of likelihood of abuse
4-MTA is abused mainly in Europe, where it appears to be part of the dance music culture. However, it is likely that its use is less widespread than it otherwise might be because of perceptions among users that the drug is stronger and more harmful than other "club drugs", such as MDMA. Abuse of 4-MTA has resulted in a number of fatalities and hospital admissions. It appears that toxic effects can be produced directly from the drug, and that the presence of other drugs or alcohol mav exacerbate such effects.
Therapeutic usefulness
4-MTA has no recognized therapeutic use.
Recommendation
4-MTA is chemically and pharmacologically similar to 4-methoxyamphetamine, MDA and MDMA. It is a relatively new synthetic drug, and was seized for the first time in 1997. Although evidence of its actual abuse is available only in several European countries, recent seizures, including those of large quantities reported from a wider range of countries, suggest that trafficking and abuse of 4-MTA have become more widespread. On the basis of this information and its similarity to known MDA-type drugs, as well as drug discrimination studies in animals, it is estimated that 4-MTA is likely to be abused so as to constitute a public health and social problem, warranting its placement under international control. Taking into consideration that 4+-MTA has no recognized therapeutic use and that it has caused a number of fatalities, the Committee concluded that abuse of 4-MTA represents an especially serious risk to public health. The Committee therefore recommended that 4-MTA be placed in Schedule I of the 1971 Convention.
ECDD Recommendation
Inclusion in Schedule I of the 1971 Convention on Psychotropic Substances
Link to full TRS
who_trs_903.pdf1.33 MB