Alternative names
Butyrylfentanyl
IUPAC Name
N-(1-phenethylpiperidin-4-yl)-N-phenylbutyramide
Current Scheduling Status
Year(s) and type of review / ECDD meetings
Drug Class
Recommendation (from TRS)
Substance identification
Chemically, butyrfentanyl is N-phenyl-N-[1-(2-phenylethyl)-4-piperidinyl] butanamide.
Previous review
Butyrfentanyl has not been previously pre-reviewed or critically reviewed by the Committee. A direct critical review was proposed based on information brought to the attention of WHO that butyrfentanyl is clandestinely manufactured, poses a risk to public health and society, and has no recognized therapeutic use by any Party.
Similarity to known substances and effects on the central nervous system
Butyrfentanyl contains a carboxamide group that can be easily hydrolysed in strong acid or strong base when heated and subsequently converted by condensation into another carboxamide such as fentanyl and to other fentanyls. Fentanyl is a Schedule I drug under the UN Single Convention on Narcotic Drugs, 1961. Similar to morphine, butyrfentanyl binds and has functional activity at the mu opioid receptor and produces antinociceptive activity in chemical and thermal assays in mice, with a potency about 1.5 times that of morphine and 30 times less than that of fentanyl. Case studies report clinical features that include typical opioid symptoms such as respiratory depression, apnoea and loss of consciousness, and one report indicated responsiveness to naloxone.
Dependence potential
Butyrfentanyl demonstrates cross-dependency in the morphine-dependent rhesus monkey. There are no reports of controlled studies of physical dependence or cross-dependency in human subjects.
Actual abuse and/or evidence of likelihood of abuse
There are no known reports of controlled studies of abuse potential in humans or laboratory animals. Butyrfentanyl, however, is actively sold through Internet websites. It has been associated with several drug seizures, and with fatal and non-fatal intoxications both in Europe and the United States. Current estimates of use are likely to be underestimates because butyrfentanyl is not included in most drug screens. Routes of administration include insufflation, rectal, intravenous and sublingual use. Re-dosing is apparently common.
Therapeutic usefulness
There are no known approved therapeutic applications for butyrfentanyl.
Recommendation
Butyrfentanyl (N-phenyl-N-[1-(2-phenylethyl)-4-piperidinyl]butanamide) is a compound liable to similar abuse and with similar ill effects to controlled opioids such as morphine and fentanyl that are included in Schedule I of the Single Convention on Narcotic Drugs, 1961. It can also be converted into fentanyl. It has no recorded therapeutic use and its use has resulted in fatalities. There is sufficient evidence that it is being or is likely to be abused so as to constitute a public health and social problem warranting the placing of the substance under international control. Thus, because it meets either of the required conditions of similarity or convertibility, it is recommended that butyrfentanyl be placed in Schedule I of the Single Convention on Narcotic Drugs, 1961, as consistent with Article 3, paragraph 3 (iii) of that Convention, in that the substance is liable to similar abuse and productive of similar ill effects to drugs in Schedule I.
Chemically, butyrfentanyl is N-phenyl-N-[1-(2-phenylethyl)-4-piperidinyl] butanamide.
Previous review
Butyrfentanyl has not been previously pre-reviewed or critically reviewed by the Committee. A direct critical review was proposed based on information brought to the attention of WHO that butyrfentanyl is clandestinely manufactured, poses a risk to public health and society, and has no recognized therapeutic use by any Party.
Similarity to known substances and effects on the central nervous system
Butyrfentanyl contains a carboxamide group that can be easily hydrolysed in strong acid or strong base when heated and subsequently converted by condensation into another carboxamide such as fentanyl and to other fentanyls. Fentanyl is a Schedule I drug under the UN Single Convention on Narcotic Drugs, 1961. Similar to morphine, butyrfentanyl binds and has functional activity at the mu opioid receptor and produces antinociceptive activity in chemical and thermal assays in mice, with a potency about 1.5 times that of morphine and 30 times less than that of fentanyl. Case studies report clinical features that include typical opioid symptoms such as respiratory depression, apnoea and loss of consciousness, and one report indicated responsiveness to naloxone.
Dependence potential
Butyrfentanyl demonstrates cross-dependency in the morphine-dependent rhesus monkey. There are no reports of controlled studies of physical dependence or cross-dependency in human subjects.
Actual abuse and/or evidence of likelihood of abuse
There are no known reports of controlled studies of abuse potential in humans or laboratory animals. Butyrfentanyl, however, is actively sold through Internet websites. It has been associated with several drug seizures, and with fatal and non-fatal intoxications both in Europe and the United States. Current estimates of use are likely to be underestimates because butyrfentanyl is not included in most drug screens. Routes of administration include insufflation, rectal, intravenous and sublingual use. Re-dosing is apparently common.
Therapeutic usefulness
There are no known approved therapeutic applications for butyrfentanyl.
Recommendation
Butyrfentanyl (N-phenyl-N-[1-(2-phenylethyl)-4-piperidinyl]butanamide) is a compound liable to similar abuse and with similar ill effects to controlled opioids such as morphine and fentanyl that are included in Schedule I of the Single Convention on Narcotic Drugs, 1961. It can also be converted into fentanyl. It has no recorded therapeutic use and its use has resulted in fatalities. There is sufficient evidence that it is being or is likely to be abused so as to constitute a public health and social problem warranting the placing of the substance under international control. Thus, because it meets either of the required conditions of similarity or convertibility, it is recommended that butyrfentanyl be placed in Schedule I of the Single Convention on Narcotic Drugs, 1961, as consistent with Article 3, paragraph 3 (iii) of that Convention, in that the substance is liable to similar abuse and productive of similar ill effects to drugs in Schedule I.
ECDD Recommendation
Inclusion in Schedule I of the 1961 Convention on Narcotic Drugs
Link to full TRS
9789241210140-eng.pdf426.09 KB
MS Questionnaire Report