U-47700
U-47700 is a synthetic opioid of the benzamide chemical class that produces analgesic, sedating, and euphoric effects.12 Developed by Upjohn in the 1970s through extensive structure-activity research, it demonstrates approximately 7.5 times the potency of morphine.31 Despite its research origins, U-47700 has very little history of human use and limited toxicity data.1 Reports indicate unusual caustic properties that may cause significant tissue damage, particularly when injected.
Contents
Dosage & Duration
Dosage
Duration
Subjective Effects
U-47700 has not been formally studied in humans, and documentation of its subjective effects rests on user reports and expectation from its opioid pharmacology. The experience is described as euphoric and mood-lifting alongside marked relaxation and pain relief. Sedation and respiratory depression are among the effects anticipated with potent opioid agonists, the latter carrying serious risk of harm or death.
Physical
Analgesia, relaxation, and sedation dominate the physical experience, accompanied by dry mouth, itching, constipation, pupil constriction, and in some cases an increased heart rate.
Autonomic
Sedation
Uncomfortable
Cognitive
The mental state is characterized by euphoria and an elevation of mood.
Reagent Testing
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Pharmacology
Pharmacodynamics
U-47700 is a selective agonist of the μ-opioid receptor, with approximately 7.5 to 10 times the potency of morphine in animal models34 despite having 2 to 4 times weaker binding affinity at all three opioid receptors.4 The compound possesses significantly lower affinity for the κ-opioid and δ-opioid receptors.4 As with other opioids, U-47700 exerts its effects by binding to and activating the μ-opioid receptor, structurally mimicking endogenous endorphins to produce analgesia, sedation, and euphoria.
Pharmacokinetics
U-47700 undergoes hepatic metabolism involving mono- and didesmethylation followed by hydroxylation.5 The desmethyl metabolites have negligible affinity for opioid receptors and are not thought to contribute to the pharmacological activity of the parent compound.64
Dangerous
Highest riskThese combinations are considered extremely harmful and should always be avoided. Reactions to these drugs taken in combination are highly unpredictable and have a potential to cause death.
Tolerance
Opioids
Harm Potential
Addiction & Dependence
Psychological
HighU-47700 has a high potential for abuse and is capable of causing psychological dependence.31 The short duration of effects combined with the addictive properties of opioids creates a strong risk of compulsive redosing.
Physical
HighPhysical dependence can develop in a short period with chronic use.7 Withdrawal symptoms emerge within 2-4 hours after the last dose and can be especially painful.7 Cravings and withdrawal effects occur if use is suddenly stopped.
Toxicity
U-47700 crystals are particularly corrosive and caustic to mucous membranes; even with regular saline washing, multiday insufflation can create bleeding sores and scabs in the septum and nasal lining that may persist for days after cessation.
History & Culture
Discovery and Development
U-47700 was developed by a research team at the Upjohn pharmaceutical company during the 1970s.9 The compound emerged from extensive work elucidating the quantitative structure-activity relationship of the benzamide scaffold. Upjohn researchers systematically…
Legality
By Country
References
Source Pages
Citations
- (October 2017). U-47700: A Clinical Review of the Literature. The Journal of Emergency Medicine, 53(4), 509–519. https://doi.org/10.1016/j.jemermed.2017.05.03412345
- (2020). U-47700 and Its Analogs: Non-Fentanyl Synthetic Opioids Impacting the Recreational Drug Market. Brain Sciences, 10(11), 895. https://doi.org/10.3390/brainsci1011089512
- (October 2017). U-47700: An Emerging Threat. Cureus, 9(10). https://doi.org/10.7759/cureus.17911234567
- (October 2020). Pharmacodynamics and pharmacokinetics of the novel synthetic opioid, U-47700, in male rats. Neuropharmacology, 177. https://doi.org/10.1016/j.neuropharm.2020.1081951234
- (January 2018). Metabolism of novel opioid agonists U-47700 and U-49900 using human liver microsomes with confirmation in authentic urine specimens from drug users. Drug Testing and Analysis, 10(1), 127–136. https://doi.org/10.1002/dta.22281
- (April 2022). Are the N-demethylated metabolites of U-47700 more active than their parent compound? In vitro μ-opioid receptor activation of N-desmethyl-U-47700 and N,N-bisdesmethyl-U-47700. Drug Testing and Analysis, 14(4), 713–717. https://doi.org/10.1002/dta.31821
- WHO Expert Committee on Drug Dependence. (2016). U-47700: Critical Review Report, 38th Expert Committee on Drug Dependence. World Health Organization. https://ecddrepository.org/en/u-47700123
- (January 2017). A case of U-47700 overdose with laboratory confirmation and metabolite identification. Clinical Toxicology, 55(1), 55–59. https://doi.org/10.1080/15563650.2016.12097671
- (4 July 1978). Patent US4098904 - Analgesic N-(2-aminocycloaliphatic)benzamides. https://patents.google.com/patent/US409890412
- (September 2016). A case of acute intoxication due to combined use of fentanyl and 3,4-dichloro-N-[2-(dimethylamino)cyclohexyl]-N-methylbenzamide (U-47700). Forensic Science International, 266, 68–72. https://doi.org/10.1016/j.forsciint.2016.05.0011
- (April 2018). Mixed intoxication by the synthetic opioid U-47700 and the benzodiazepine flubromazepam with lethal outcome: Pharmacokinetic data. Drug Testing and Analysis, 10(8), 1336–1341. https://doi.org/10.1002/dta.23911
- WHO Expert Committee on Drug Dependence. (November 2016). U-47700 Critical Review Report, 38th ECDD Meeting, WHO (2016). https://ecddrepository.org/sites/default/files/4.1_u-47700_critreview.pdf1
- (May 3, 2017). The Misuse of Drugs Act 1971 (Amendment) Order 2017 (SI 2017/634). UK Government. https://www.legislation.gov.uk/uksi/2017/634/made1
- Drug Enforcement Administration. (November 14, 2016). Schedules of Controlled Substances: Temporary Placement of U-47700 Into Schedule I. Federal Register. https://www.govinfo.gov/content/pkg/FR-2016-11-14/pdf/2016-27357.pdf1
- (20 April 2018). Schedules of Controlled Substances: Placement of Butyryl Fentanyl and U-47700 Into Schedule I. Federal Register. https://www.federalregister.gov/documents/2018/04/20/2018-08280/schedules-of-controlled-substances-placement-of-butyryl-fentanyl-and-u-47700-into-schedule-i1
Further Reading
Automated synthesisInformation aggregated and synthesized using an autonomous workflow built by Josie Kins.
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