Furanylfentanyl
Furanylfentanyl is a potent synthetic opioid analgesic of the anilinopiperidine class and a structural analogue of fentanyl.12 Classified as a research chemical, it has extremely limited pharmacological and toxicological documentation available. It is thought to be somewhat less potent and shorter-acting than butyrfentanyl. Due to the scarcity of reliable information and its high potency, exercising extreme caution with this substance is strongly recommended.
Contents
Dosage & Duration
Dosage
Duration
Subjective Effects
The experience is that of a short-acting, extremely potent opioid, dominated by analgesia, sedation, and the characteristic opioid sense of physical and emotional comfort. Its effects closely mirror those of fentanyl itself, though it is roughly half as potent and believed to be somewhat shorter in duration than related analogs such as butyrfentanyl. The margin between an active dose and dangerous respiratory depression is narrow, and sensory alteration beyond bodily sensation is minimal.
Physical
Physical effects follow the fentanyl-analog pattern: pain relief and heavy sedation accompanied by itching and nausea, with potentially life-threatening respiratory depression at higher doses.
Cognitive
The headspace is one of opioid sedation and relief, with little in the way of complex cognitive alteration reported.
Reagent Testing
Loading reagent data
Pharmacology
Pharmacodynamics
Furanylfentanyl is an opioid analgesic and a structural analog of fentanyl.34 It exhibits an ED50 of 0.02 mg/kg in mice, and in humans it has been estimated to be 50 to 100 times more potent than morphine, placing it at roughly half the potency of fentanyl.
Pharmacokinetics
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.
Unsafe
AvoidThere is considerable risk of physical harm when taking these combinations, they should be avoided where possible.
Caution
Use cautionThese combinations are not usually physically harmful, but may produce undesirable effects, such as physical discomfort or overstimulation. Extreme use may cause physical health issues. Synergistic effects may be unpredictable. Care should be taken when choosing to use this combination.
Tolerance
Opioids (full cross-tolerance expected with all μ-opioid receptor agonists)
Harm Potential
Addiction & Dependence
Psychological
HighClassified as habit-forming. As a potent fentanyl analog, it carries significant risk of psychological dependence consistent with other opioids.5
Toxicity
Potentially serious respiratory depression can occur at active doses and is life-threatening; this is the primary mechanism of fatal opioid overdose and represents the most significant acute risk with this substance.5
History & Culture
Furanylfentanyl was first characterized during research conducted in the 1980s, when studies in humans demonstrated it to be approximately 50 to 100 times more potent than morphine, placing it at roughly half the potency of fentanyl.8 Despite this early…
Legality
By Country
References
Source Pages
Citations
- (May 2022). In vitro and in vivo pharmaco-dynamic study of the novel fentanyl derivatives: Acrylfentanyl, Ocfentanyl and Furanylfentanyl. Neuropharmacology, 209. https://doi.org/10.1016/j.neuropharm.2022.1090201
- (2022). The Genotoxicity of Acrylfentanyl, Ocfentanyl and Furanylfentanyl Raises the Concern of Long-Term Consequences. 23(22), 14406. https://doi.org/10.3390/ijms2322144061
- (n.d.). In Vitro and In Vivo Pharmacological Characterization of Fentanyl Analogs. https://pmc.ncbi.nlm.nih.gov/articles/PMC12408109/1
- (n.d.). Fentanyl decreases blood oxygen more than furanylfentanyl despite similar effects on breathing. https://pmc.ncbi.nlm.nih.gov/articles/PMC12869654/1
- (20 April 2016). Intoxications involving the fentanyl analogs acetylfentanyl, 4-methoxybutyrfentanyl and furanylfentanyl: results from the Swedish STRIDA project. Clinical Toxicology, 54(4), 324–332. https://doi.org/10.3109/15563650.2016.113971512345
- (July 2015). Fentanyls: Are we missing the signs? Highly potent and on the rise in Europe. The International Journal on Drug Policy, 26(7), 626–631. https://doi.org/10.1016/j.drugpo.2015.04.0031
- (September 2016). Notes from the Field: Furanyl-Fentanyl Overdose Events Caused by Smoking Contaminated Crack Cocaine - British Columbia, Canada, July 15-18, 2016. MMWR. Morbidity and Mortality Weekly Report, 65(37), 1015–1016. https://doi.org/10.15585/mmwr.mm6537a612
- (6 May 2023). Fentanyl and other New Psychoactive Synthetic Opioids. Challenges to Prevention and Treatment. Revista de Investigación Clínica, 75(3), 93–104. https://doi.org/10.24875/ric.2300010912
- Preckwinkle T. (2016). Medical Examiner Reports Deaths from Powerful Opioids on the Rise. Cook County Government. https://www.cookcountyil.gov/news/medical-examiner-reports-deaths-powerful-opioids-rise1
Further Reading
Calderon SN et al., Respiratory ED50 comparison (PMID 34673011)
CDC HAN alert on fentanyl-laced pills (2016)
CDC MMWR: Furanylfentanyl Crack-Cocaine Overdose Cluster, BC 2016
DEA Final Order: Furanylfentanyl Schedule I (83 FR 61320)
DHS Master Question List: Synthetic Opioids (2024)
DrugWatch Information Sheet: Fentanyls (2017)
EMCDDA Risk Assessment Report: Furanylfentanyl (2017)- Goggin et al.: Furanylfentanyl Metabolites in Urine, J Anal Toxicol (2017)
- Guerrieri et al.: Postmortem Findings in Furanylfentanyl Deaths, J Anal Toxicol (2017)
- Hudson S et al.: μ-Receptor Affinity Study (PMID 33091380)
- Mohr AL et al.: Furanylfentanyl Fatalities, J Anal Toxicol 40(9):709-717 (2016)
- PubChem: 11957557
- PubChem: Furanylfentanyl (CID 13653606)
UNODC: Fentanyl Analogues Identification Methods (2017)- Watanabe et al.: Furanylfentanyl Metabolism, Forensic Toxicol (2017)
Automated synthesisInformation aggregated and synthesized using an autonomous workflow built by Josie Kins.
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