Background/Objective: We report on a case of severe intoxication after insufflation of
U-47700, a synthetic opioid that acts as a selective agonist of the μ-opioid receptor, and is several
times more potent than morphine. A man in his 30s was found irresponsive in his apartment and was
brought to the emergency department of a local hospital. A comatose state and severe respiratory depression
were present. Hetero anamnesis revealed that the patient could have taken the substance
named “U-47700”, bought on the Internet. After supportive care, the patient fully recovered.
Method: Urine, blood and a white powder found at his home were collected during his hospital stay
and sent for testing using liquid chromatography-high resolution mass spectrometry (LC-HRMS) on an
Orbitrap instrument. Later, his pubic hair was also collected. A standard comprehensive toxicology
screening was performed.
Results: U-47700 was identified in all biological samples and in the seized white powder. Using liquid
chromatography-high resolution mass spectrometry (LC-HRMS) the presence of U-47700 and its
phase I and phase II metabolites in blood, urine and pubic hair was confirmed. U-47700 was determined
at 94 ng/mL and 5.2 ng/mL in blood at the admission and the day after, respectively, and 3.02
ng/mg in pubic hair, together with its metabolites. No other opioid nor designer drug could be detected
in blood and urine, while in pubic hair Cocaine, Benzoylecgonine, Norcocaine, Mephedrone, Ketamine,
Norketamine, 3,4-Methylenedioxymethamphetamine, Tetrahydrocannabinol and Cannabinol
were also detected.
Conclusion: The toxicological findings confirmed the use of U-47700 in the intoxicated patient and
also revealed a history of a poly-drug use. The use of LC-HRMS allowed the easy identification of the
NPS and its metabolites in fluids and hair.