Pharmacokinetics, pharmacodynamics and toxicology of new psychoactive substances (NPS): 2C-B, 4-fluoroamphetamine and benzofurans

Drug Alcohol Depend. 2015 Dec 1:157:18-27. doi: 10.1016/j.drugalcdep.2015.10.011. Epub 2015 Oct 22.


Background: Recently, the number of new psychoactive substances (NPS) appearing on the illicit drug market has shown a marked increase. Although many users perceive the risk of using NPS as medium or low, these substances can pose a serious health risk and several NPS have been implicated in drug-related deaths. In Europe, frequently detected NPS are 4-bromo-2,5-dimethoxyphenethylamine (2C-B), 4-fluoroamphetamine (4-FA) and benzofurans (5-(2-aminopropyl)benzofuran (5-APB) or 6-(2-aminopropyl)benzofuran (6-APB)). However, little is known about the health risks of these specific NPS.

Methods: In this paper, existing literature on the pharmacokinetics and pharmacodynamics of 2C-B, 4-FA and benzofurans (5-APB/6-APB) was reviewed.

Results: Our review showed that the clinical effects of 2C-B, 4-FA and benzofurans (5-APB/6-APB) are comparable with common illicit drugs like amphetamine and 3,4-methylenedioxymethamphetamine (MDMA). Therefore, NPS toxicity can be handled by existing treatment guidelines that are based on clinical effects instead of the specific drug involved. Even so, information on the health risks of these substances is limited to a number of case reports that are complicated by confounders such as analytical difficulties, mislabelling of drugs, concomitant exposures and interindividual differences.

Conclusion: To aid in early legislation, data on clinical effects from poisons centres and user fora should be combined with (in vitro) screening methods and collaboration on an (inter)national level is essential. As a result, potentially hazardous NPS could be detected more quickly, thereby protecting public health.

Keywords: Clinical; Designer drugs; Legal highs; Research chemicals; Toxicology.

Publication types

  • Review

MeSH terms

  • Amphetamines / adverse effects*
  • Amphetamines / pharmacokinetics*
  • Benzofurans / adverse effects*
  • Benzofurans / pharmacokinetics*
  • Dimethoxyphenylethylamine / adverse effects
  • Dimethoxyphenylethylamine / analogs & derivatives*
  • Dimethoxyphenylethylamine / pharmacokinetics
  • Humans
  • Illicit Drugs / adverse effects
  • Illicit Drugs / pharmacokinetics
  • Psychotropic Drugs / adverse effects*
  • Psychotropic Drugs / pharmacokinetics*


  • Amphetamines
  • Benzofurans
  • Dimethoxyphenylethylamine
  • Illicit Drugs
  • Psychotropic Drugs
  • 4-fluoroamphetamine
  • 2-(4-bromo-2,5-dimethoxyphenyl)ethylamine