4-Fluoroisobutyrylfentanyl (also known as 4-FIBF and p-FIBF) is an
opioidanalgesic that is an
analog of
butyrfentanyl and structural isomer of
4-Fluorobutyrfentanyl and has been sold online as a
designer drug.[1][2][3][4][5] It is closely related to
4-fluorofentanyl, which has an EC50 value of 4.2 nM for the human
μ-opioid receptor.[6] 4-fluoroisobutyrylfentanyl is a highly selective μ-opioid receptor agonist whose analgesic potency is almost ten times of that reported for morphine.[7]
Side effects
Side effects of
fentanyl analogs are similar to those of fentanyl itself, which include
itching,
nausea and potentially serious
respiratory depression, which can be life-threatening. Fentanyl analogs have killed hundreds of people throughout Europe and the former Soviet republics since the most recent resurgence in use began in Estonia in the early 2000s, and novel derivatives continue to appear.[8]
^Helander A, Bäckberg M, Signell P, Beck O (July 2017). "Intoxications involving acrylfentanyl and other novel designer fentanyls - results from the Swedish STRIDA project". Clinical Toxicology. 55 (6): 589–599.
doi:
10.1080/15563650.2017.1303141.
PMID28349714.
S2CID11978059.
^Pardi J, Toriello A, Cooper G (January 2020). "Evaluation of 4-fluoroisobutyrylfentanyl in blood samples from 247 authentic cases submitted to the New York City Office of Chief Medical Examiner in 2017–2018". Forensic Toxicology. 38 (2): 340–351.
doi:
10.1007/s11419-019-00518-6.
ISSN1860-8973.
S2CID210135027.
^Mounteney J, Giraudon I, Denissov G, Griffiths P (July 2015). "Fentanyls: Are we missing the signs? Highly potent and on the rise in Europe". The International Journal on Drug Policy. 26 (7): 626–31.
doi:
10.1016/j.drugpo.2015.04.003.
PMID25976511.