Recommendation (from TRS)
Substance identification
Butonitazene (IUPAC name: N,N-diethyl-2-[(4-butoxyphenyl)methyl]-5-nitro-1H-benzimidazole-1-
ethanamine), also known as butoxynitazene, is a benzimidazole-derived synthetic opioid.
Butonitazene is found as a crystalline solid and a white or yellow-brown powder.
WHO review history
Butonitazene has not been reviewed formally by WHO and is not currently under international
control. Information was brought to WHO’s attention that this substance is manufactured
clandestinely, poses a risk to public health and has no recognized therapeutic use.
Similarity to known substances and effects on the central nervous system
The chemical structure and pharmacological effects of butonitazene are similar to those of opioid
drugs such as etonitazene and isotonitazene that are controlled under Schedule I of the United
Nations Conventions on Narcotic Drugs of 1961. Butonitazene is an agonist at μ-opioid receptors and
has similar analgesic effects as morphine and fentanyl.
Dependence potential
No studies in experimental animal or humans were found on the dependence potential of
butonitazene; however, as it is a μ-opioid receptor agonist, it would be expected to produce
dependence.
Actual abuse and/or evidence of likelihood of abuse
No studies on the abuse potential of butonitazene in humans were found. In an animal model
predictive of abuse potential, butonitazene had morphine-like effects, which were blocked by the
opioid antagonist naltrexone. As it is a μ-opioid receptor agonist, it would be expected to produce
euphoria and other effects predictive of high abuse liability.
Butonitazene is reported to be administered by various routes, including smoking, intranasally and by
injection. Non-fatal intoxications that involved butonitazene and required hospitalization have been
reported.
Seizures of butonitazene have been reported in multiple countries in two regions.
Therapeutic use
Butonitazene is not known to have any therapeutic use and has never been marketed as a medicinal
product.
Rationale and recommendation
Butonitazene, also known as butoxynitazene, is a synthetic opioid that is liable to abuse and to
production of ill effects similar to those of other opioids that are controlled under Schedule I of the
ECDD Recommendation
Inclusion in Schedule I of the 1961 Convention on Narcotic Drugs