Fatal poisoning with a new phenylethylamine: 4-methylthioamphetamine (4-MTA)

J Anal Toxicol. 2000 Mar;24(2):85-9. doi: 10.1093/jat/24.2.85.


There has been much publicity in the United Kingdom regarding a new phenylethylamine-based compound called 4-methylthioamphetamine (4-MTA), also known as para-methylthioamphetamine (p-MTA), MTA or "Flatliner". Chemically, 4-MTA is an amphetamine derivative and is a non-neurotoxic potent serotonin-releasing agent and reversible inhibitor of rat monoamine oxidase-A. Analysis of postmortem blood and urine specimens in a case implicating 3,4-methylenedioxymethamphetamine revealed the presence of 4-MTA at a concentration of 4.6 mg/L in femoral blood and 87.2 mg/l in the urine. The concentration of 4-MTA in perimortem blood was measured at 4.2 mg/L. This is the first reported case of death involving 4-MTA in the United Kingdom and the first case known to involve 4-MTA only.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Amphetamines / metabolism
  • Amphetamines / poisoning*
  • Enzyme Multiplied Immunoassay Technique
  • Fatal Outcome
  • Gas Chromatography-Mass Spectrometry
  • Humans
  • Male
  • Poisoning / blood*
  • Poisoning / urine*
  • Selective Serotonin Reuptake Inhibitors / metabolism
  • Selective Serotonin Reuptake Inhibitors / poisoning*
  • Substance Abuse Detection / methods


  • Amphetamines
  • Serotonin Uptake Inhibitors
  • 4-methylthioamphetamine