U-47700: A Not So New Opioid

Abstract

U-47700 was developed by the Upjohn Co. in the 1970s as part of their search for a selective μ-opioid agonist with similar potency as morphine. U-47700 has re-emerged recently in the illicit drug market and is easily and cheaply obtained via the internet as well as on the street, many times falsely sold as another drug. Several fatalities from U-47700 have been reported in scientific literature, often in combination with other intoxicants. This case report describes the first death in south-central Kansas resulting solely from U-47700 intoxication: a 26-year-old white male found dead in his bedroom with apparent drug paraphernalia. Autopsy findings were consistent with opioid overdose, but toxicological examination, utilizing immunoassay and instrumental techniques, was negative for opioids. U-47700 was detected in a comprehensive alkaloid screen by GC/MS and GC-NPD, and quantitation was performed using GC-NPD on a variety of specimens to provide a full tissue distribution. Quantitation of U-47700 in this individual revealed the following: heart blood 0.26 mg/L, femoral blood 0.40 mg/L, vitreous fluid 0.09 mg/L, brain 0.38 mg/kg, liver 0.28 mg/kg and urine 4.6 mg/L.

Postmortem Toxicology of New Synthetic Opioids

“…MT-45 references: (Papsun et al, 2016 ; Fels et al, 2017 ) . U-47700 references: (Elliott et al, 2016 ; Mohr et al, 2016 ; Dziadosz et al, 2017 ; Papsun et al, 2017 ; Rohrig et al, 2017 ) .…”

Near‐fatal Intoxication with the “New” Synthetic Opioid U‐47700: The First Reported Case in the Czech Republic

“…However, fatal intoxications with much lower serum levels have been reported as 190 ng/mL and 13.8 ng/mL , although attribution of death to U‐47700 in the latter case has been debated . In other fatal intoxications, postmortem peripheral blood/serum levels have been reported as between 17 and 490 ng/mL (across multiple cases, 5), 400 ng/mL , 526 ng/mL, and 819 ng/mL and as high as 1460 ng/mL although the latter has been questioned . The serum concentration identified in the present case study is therefore consistent with that found in nonfatal and some fatal cases.…”

“…U‐47700 ( 3,4‐ dichloro‐N‐(2‐(dimethylamino)cyclohexyl)‐N‐methylbenzamide) is a powerful synthetic opioid that is readily available for purchase via the internet and is often present as a co‐ingredient in street heroin, and counterfeit analgesics . U‐47700 is associated with a growing number of fatalities , near‐fatalities, and acute intoxications .…”

Fatalities caused by novel opioids: a review

“…(2017) [60]U-47700 fatality in Wichita, Kansas (USA)GC-MS-SIMBlood (f) 0.4 ng/mL; blood (h) 0.26 ng/mL; urine 4.6 ng/mL; VH 0.09 ng/mL; liver 0.28 ng/mgYoung male obese drug user with enlarged heart and oedematous, congested lungs; THC Blood (h) 19 ng/mL, possible trace phencyclidineRohrig et al. (2017) [82]Three acrylfentanyl fatalities (one also with furanylfentanyl) in Charleston, South Carolina (USA)GC-MS-SIMAcrylfentanyl: blood (p) 0.3, 0.95 and 0.32 ng/mLFuranylfentanyl: blood (p) 0.95 ng/mL (case 3)Three male drug users, all with other drugs detected. LOQ 0.1 ng/mLButler et al.…”

“…These and seven other publications in 2017 found blood concentrations of U-47700 ranging from 0.4 ng/mL to 1.46 mg/L with a median of around 0.3 mg/L (Table 1). As with other opioids most had other drugs present including the case report from the USA in which the stimulant 3-fluorophenmetrazine was also detected [81], and in another, of a morbidly obese man with an enlarged heart [82]. Survival from use of this opioid has also been reported: all patients showed classical signs of opioid toxicity [83,84].…”