VIENNA, Austria – 14 May 2026:
Identification, classification, and toxicological risk profile
It is structurally distinct from other opioids like
fentanyls and
nitazenes. Recent
pharmacological studies [1] demonstrate µ-opioid receptor activity, with potency exceeding fentanyl, and activity at κ‑ and δ-opioid receptors. In vivo studies in mice have shown that cychlorphine causes profound respiration and cardiovascular depression at lower doses than fentanyl.
Global availability and detection in drug samples and postmortem cases
Interestingly, a recent
research bulletin identified orphine (brorphine-like) synthetic opioids as being available on Australian and international cryptomarkets, indicating online supply and cross-border distribution. The most frequently identified orphines in this digital drug market were
5,6-dichloro desmethylchlorphine (48%), followed by
spirochlorphine (26%) and
cychlorphine (23%).
Examples of health alerts and reports on cychlorphine across different countries are:
Reports submitted to UNODC EWA on drug samples indicate that cychlorphine is typically found as powders (white/beige/brown) and tablets, with onereport of blotter paper. Based on the reported
toxicology data, there have been a total of 78 cychlorphine-related post-mortem cases (from the USA and the UK). The median post-mortem blood concentration was 29 ng/mL (range: 5-183 ng/mL) analysed largely by LC-MS instrumentation with confirmation using a reference standard. Most cases involved polysubstance toxicity, other new psychoactive substances (NPS) found included nitazenes, other orphine analogues, xylazine, benzodiazepines, medetomidine, and
N,N-dimethylamphetamine.
The appearance of cychlorphine follows
earlier detections of brorphine and other orphine analogues, consistent with adaptive substitution within illicit opioid markets. It has been detected in drug samples mixed with other illicit substances, particularly fentanyl and analogues, heroin, cocaine, and medetomidine. Similarly to many other synthetic opioids, cychlorphine has been found in falsified pharmaceuticals such as
Xanax®,
Percocet®,
Dilaudid®, and
OxyContin® tablets.
Analytical challenges, legal context, and public health significance
Cychlorphine is not expected to be detected by standard drug test strips or routine opioid urine screens, posing challenges for clinical diagnosis and surveillance, and contributing to heightened risk. The detection and identification of new synthetic opioids and their metabolites may require analytical methods beyond standard screening techniques in routine testing laboratories.
Given some limitations in comprehensive and available spectral libraries used in
preliminary screening methods for emerging drugs, testing laboratories could explore or expand on various targeted and non-targeted analytical techniques such as LC-HRMS (e.g., LC-QTOF-MS), LC-MS/MS, and NMR. With its high potency and potential presence in polysubstance samples, testing laboratories should aim to adopt broad screening workflows with confirmatory testing, ensuring low limits of detection and maintaining updated reference libraries and spectra for orphine analogues.
The recent reports reinforce the importance of early awareness, analytical preparedness, and information sharing across forensic, public health, and law enforcement systems. Cychlorphine as an emerging threat to public health calls to improve the accessibility and availability of health prevention and intervention opportunities such as naloxone use and treatment. As an opioid antagonist, naloxone rapidly reverses opioid effects (see
UNODC-WHO S-O-S initiative), however,
further research is needed as there are observed differences in sensitivity to naloxone for different orphine analogues.
From a legal aspect, the latest
ACMD report recommends generic definitions and individual substance listings to be introduced in the UK to capture the broader orphine class similar to the current approach used for nitazenes. The report also discusses the generic approach used by Germany in the
New Psychoactive Substances Act (NpSG). Cychlorphine is recognised as a dangerous emerging drug threat with potential for further geographical spread to other international regions.
For more information on UNODC EWA News:
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[1] Pharmacological and analytical information is available to users who are logged into EWA