Forensic Toxicology

, Volume 36, Issue 2, pp 233–242 | Cite as

Diphenidine: a dissociative NPS makes an entrance on the drug scene

  • Maria Katselou
  • Ioannis Papoutsis
  • Panagiota NikolaouEmail author
  • Nektaria Misailidi
  • Chara Spiliopoulou
  • Sotiris Athanaselis
Review Article



Diphenidine is a potent synthetic dissociative anesthetic drug that has recently emerged in drug markets of Europe, Japan and America. The aim of this review is to summarize the current knowledge about this drug concerning its chemistry, synthesis, prevalence, pharmacology, toxicology and metabolism, as well as its legal status. Analytical methodologies developed for the determination of diphenidine in biological specimens and published diphenidine-related intoxications, fatal or not, are also presented.


All the reviewed information was gathered through a detailed search of PubMed and the World Wide Web using proper keywords.


Diphenidine is not approved for medical or veterinary use, but it is used illicitly around the world for recreational purposes or as a substitute of other controlled dissociative drugs. It is available through the Internet in powder form for oral administration, smoking or vaporization. Since its first appearance in the drug market in 2013, seizures have been reported worldwide and its abuse has already caused intoxications and deaths in Europe and Japan, thus leading to its scheduling in the United Kingdom and Canada during the second semester of 2016.


Diphenidine is a harmful dissociative drug that recently gained serious concern for public health. International and local authorities should take all the appropriate actions and measures to avoid the expansion of this new threat.


Diphenidine Dissociatives NPS Pharmacology and toxicology Metabolism Legal status 


Compliance with ethical standards

Conflict of interest

There are no financial or other relations that could lead to a conflict of interest.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.


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Copyright information

© Japanese Association of Forensic Toxicology and Springer Japan KK, part of Springer Nature 2018

Authors and Affiliations

  • Maria Katselou
    • 1
  • Ioannis Papoutsis
    • 1
  • Panagiota Nikolaou
    • 1
    Email author
  • Nektaria Misailidi
    • 1
  • Chara Spiliopoulou
    • 1
  • Sotiris Athanaselis
    • 1
  1. 1.Department of Forensic Medicine and Toxicology, School of MedicineNational and Kapodistrian University of AthensAthensGreece

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