English: Tetrahydrofuranylfentanyl is an opioid analgesic that is an analog of fentanyl and has been sold online as a designer drug, first appearing in Europe in late 2016.
Tetrahydrofuranylfentanyl is an opioid analgesic that is an analog of fentanyl and has been sold online as a designer drug, first appearing in Europe in late 2016.