IUPAC Name
1-(2H-1,3-Benzodioxol-5-yl)-2-(ethylamino)pentan-1-one
Current Scheduling Status
Schedule I of the 1961 Convention on Narcotic Drugs
Year(s) and type of review / ECDD meetings
Drug Class
Recommendation (from TRS)
Substance identification
Para-fluoro-butyrylfentanyl (N-(4-fluorophenyl)-N-[1-(2-phenylethyl)piperidin- 4-yl]butanamide) is a synthetic analogue of the opioid analgesic fentanyl. Samples obtained from seizures and from other sources suggest that para-fluoro- butyrylfentanyl is available in the form of a powder, tablet, nasal spray and a preparation for vaping.
WHO review history
Para-fluoro-butyrylfentanyl has not been previously pre-reviewed or critically reviewed by the WHO ECDD. A direct critical review was proposed based on information brought to WHO’s attention that para-fluoro-butyrylfentanyl poses a serious risk to public health and has no recognized therapeutic use.
Similarity to known substances and effects on the central nervous system
Para-fluoro-butyrylfentanyl has a higher affinity to μ-opioid receptors than to κ- and δ-opioid receptors and has been shown to act as a partial agonist at the μ-opioid receptor. In animals, it produces typical opioid effects, including analgesia, with a potency between that of morphine and fentanyl. In cases of non- fatal intoxication in humans, para-fluoro-butyrylfentanyl has produced signs and symptoms such as disorientation, slurred speech, unsteady gait, hypotension and pupil constriction that are consistent with an opioid mechanism of action.
Para-fluoro-butyrylfentanyl can be readily converted to its isomer para- fluoro-isobutyrylfentanyl (N-(4-fluorophenyl)-2-methyl-N-[1-(2-phenylethyl) piperidin-4-yl]propanamide), which is an opioid listed in Schedule I of the 1961 Single Convention on Narcotic Drugs.
Dependence potential
There are no studies of the dependence potential of this substance in humans or laboratory animals. However, based on its mechanism of action, para-fluoro- butyrylfentanyl would be expected to produce dependence similar to other opioid drugs.
Actual abuse and/or evidence of likelihood of abuse
No controlled studies of the abuse potential of para-fluoro-butyrylfentanyl have been reported and there is very little information on the extent of its abuse. The substance has been detected in biological samples obtained in cases of fatal and non-fatal intoxication. Fatalities have been reported in some countries where the compound has been identified in biological fluids in combination with other drugs. There have also been cases where death has been attributed to the effects of para-fluoro-butyrylfentanyl.
Therapeutic usefulness
Para-fluoro-butyrylfentanyl is not known to have any therapeutic uses.
Recommendation
Para-fluoro-butyrylfentanyl is an opioid receptor agonist that has significant potential for dependence and likelihood of abuse. The limited evidence available indicates that it has adverse effects typical of opioids, which include the potential to cause death due to respiratory depression. Para-fluoro-butyrylfentanyl has caused substantial harm and has no therapeutic use. It is liable to similar abuse and produces similar ill-effects to those of many other opioids placed in Schedule I of the 1961 Single Convention on Narcotic Drugs:
■■ Recommendation: The Committee recommended that para- fluoro-butyrylfentanyl (N-(4-fluorophenyl)-N-[1-(2-phenylethyl) piperidin-4-yl]butanamide) be added to Schedule I of the 1961 Single Convention on Narcotic Drugs.
Para-fluoro-butyrylfentanyl (N-(4-fluorophenyl)-N-[1-(2-phenylethyl)piperidin- 4-yl]butanamide) is a synthetic analogue of the opioid analgesic fentanyl. Samples obtained from seizures and from other sources suggest that para-fluoro- butyrylfentanyl is available in the form of a powder, tablet, nasal spray and a preparation for vaping.
WHO review history
Para-fluoro-butyrylfentanyl has not been previously pre-reviewed or critically reviewed by the WHO ECDD. A direct critical review was proposed based on information brought to WHO’s attention that para-fluoro-butyrylfentanyl poses a serious risk to public health and has no recognized therapeutic use.
Similarity to known substances and effects on the central nervous system
Para-fluoro-butyrylfentanyl has a higher affinity to μ-opioid receptors than to κ- and δ-opioid receptors and has been shown to act as a partial agonist at the μ-opioid receptor. In animals, it produces typical opioid effects, including analgesia, with a potency between that of morphine and fentanyl. In cases of non- fatal intoxication in humans, para-fluoro-butyrylfentanyl has produced signs and symptoms such as disorientation, slurred speech, unsteady gait, hypotension and pupil constriction that are consistent with an opioid mechanism of action.
Para-fluoro-butyrylfentanyl can be readily converted to its isomer para- fluoro-isobutyrylfentanyl (N-(4-fluorophenyl)-2-methyl-N-[1-(2-phenylethyl) piperidin-4-yl]propanamide), which is an opioid listed in Schedule I of the 1961 Single Convention on Narcotic Drugs.
Dependence potential
There are no studies of the dependence potential of this substance in humans or laboratory animals. However, based on its mechanism of action, para-fluoro- butyrylfentanyl would be expected to produce dependence similar to other opioid drugs.
Actual abuse and/or evidence of likelihood of abuse
No controlled studies of the abuse potential of para-fluoro-butyrylfentanyl have been reported and there is very little information on the extent of its abuse. The substance has been detected in biological samples obtained in cases of fatal and non-fatal intoxication. Fatalities have been reported in some countries where the compound has been identified in biological fluids in combination with other drugs. There have also been cases where death has been attributed to the effects of para-fluoro-butyrylfentanyl.
Therapeutic usefulness
Para-fluoro-butyrylfentanyl is not known to have any therapeutic uses.
Recommendation
Para-fluoro-butyrylfentanyl is an opioid receptor agonist that has significant potential for dependence and likelihood of abuse. The limited evidence available indicates that it has adverse effects typical of opioids, which include the potential to cause death due to respiratory depression. Para-fluoro-butyrylfentanyl has caused substantial harm and has no therapeutic use. It is liable to similar abuse and produces similar ill-effects to those of many other opioids placed in Schedule I of the 1961 Single Convention on Narcotic Drugs:
■■ Recommendation: The Committee recommended that para- fluoro-butyrylfentanyl (N-(4-fluorophenyl)-N-[1-(2-phenylethyl) piperidin-4-yl]butanamide) be added to Schedule I of the 1961 Single Convention on Narcotic Drugs.
ECDD Recommendation
Inclusion in Schedule I of the 1961 Convention on Narcotic Drugs
Link to full TRS
9789241210270-eng.pdf453.93 KB
MS Questionnaire Report