Tetrahydrofuranylfentanyl is a designer drug that emerged in Europe in late 2016. It is classified as an opioid analgesic and is structurally related to fentanyl.

IUPAC name
CAS Number2142571-01-3
PubChem CID137332293
Chemical and physical data
Molar mass378.516 g·mol−1

Side effects

The side effects associated with fentanyl analogues closely resemble those of fentanyl itself, encompassing symptoms such as itching, nausea, and the potential for severe respiratory depression, which poses a life-threatening risk. Fentanyl analogues have claimed the lives of numerous individuals across Europe and the former Soviet republics. The resurgence in their use began in Estonia during the early 2000s, and the emergence of novel derivatives remains a concern.
A new wave of fentanyl analogues entered the scene around 2014 in the United States, steadily gaining prevalence. Since 2016, these substances have been responsible for a substantial number of overdose deaths every week.

Legal status

Tetrahydrofuranylfentanyl was classified as a Schedule I substance in the United States in October 2017 to prevent an imminent threat to public safety.


1. What is Tetrahydrofuranylfentanyl (THF-F)?

Tetrahydrofuranylfentanyl, often abbreviated as THF-F, is a synthetic opioid that belongs to the fentanyl analogue family. It is chemically related to fentanyl, a powerful synthetic opioid painkiller. THF-F is known for its potent analgesic effects.

2. How and when did Tetrahydrofuranylfentanyl emerge?

Tetrahydrofuranylfentanyl first emerged as a designer drug in Europe in late 2016. Since its introduction, it has gained attention due to its potent opioid properties and association with overdose cases.

3. Are there any studies on the metabolism of Tetrahydrofuranylfentanyl?

Yes, research conducted in December 2019 investigated the metabolism of Tetrahydrofuranylfentanyl in human hepatocytes. This study aimed to detect and confirm the presence of metabolites, providing insights into how the drug is processed in the human body.

4. Why are fentanyls like Tetrahydrofuranylfentanyl a concern?

Fentanyls, including Tetrahydrofuranylfentanyl, are a concern due to their high potency and potential for severe side effects. These substances can cause itching, nausea, and, most critically, life-threatening respiratory depression. They have been associated with numerous overdose cases and even fatalities.

5. What is the legal status of Tetrahydrofuranylfentanyl?

To address public safety concerns, Tetrahydrofuranylfentanyl was placed into Schedule I of controlled substances in the United States in October 2017. This classification reflects its high risk and potential harm.

6. Are there other related fentanyl analogues of concern?

Yes, various fentanyl analogues, including novel synthetic opioids, have raised concerns worldwide. These substances continue to appear, leading to a global challenge of managing their risks and consequences.

7. How can one stay safe and informed about Tetrahydrofuranylfentanyl and similar substances?

To stay safe and informed, it is essential to avoid the use of illicit substances, especially fentanyl analogues. Be cautious about any unfamiliar or unregulated drugs, as they can pose significant health risks. Keeping up with the latest research and government advisories can help individuals make informed choices about their well-being.


  1. EMCDDA–Europol Joint Report on THF-F (2017): This joint report focuses on the new psychoactive substance N-phenyl-N-[1-(2-phenylethyl)piperidin-4-yl]tetrahydrofuran-2-carboxamide, commonly referred to as Tetrahydrofuranylfentanyl (THF-F). The report provides valuable insights into this synthetic opioid substance, shedding light on its properties and potential risks. (September 2017)
  2. Metabolism Study (2019): This study delves into the metabolism of Tetrahydrofuranylfentanyl. It explores how the human body processes this synthetic opioid, including the detection and confirmation of ring-opened metabolites. Understanding the metabolic pathways of THF-F is crucial for assessing its effects on health. (December 2019)
  3. Fentanyls in Europe (2015): This report discusses the presence and rise of highly potent fentanyl analogs, including THF-F, in Europe. It raises awareness of the growing use of these substances and their potential public health implications. (July 2015)
  4. Comprehensive Review of Fentanyls (2017): This comprehensive review focuses on fentanyl, its analogs, and novel synthetic opioids. It provides an in-depth examination of the properties, risks, and impact of these substances. Understanding the characteristics of THF-F and similar drugs is essential for informed decision-making regarding their use. (October 2017)
  5. DEA Temporary Scheduling Order (2017): The Drug Enforcement Administration (DEA) issued a temporary scheduling order related to Tetrahydrofuranylfentanyl and other fentanyl analogs. This order aimed to address public safety concerns by placing certain substances into Schedule I of controlled substances. (October 2017)

Leave a Comment

Your email address will not be published. Required fields are marked *