The synthesis of clonazolam was first reported in 1971 and the drug was described as the most active compound in the series tested.
Clonazolam is reported to be highly potent, and concerns have been raised that clonazolam and flubromazolam in particular may pose comparatively higher risks than other designer benzodiazepines, due to their ability to produce strong sedation and amnesia at oral doses of as little as 0.5 mg.
Virginia State Law has declared all of the following are now schedule I: clonazolam, etizolam, flualprazolam, flubromazolam, and flubromazepam.
Clonazolam and flualprazolam are schedule I controlled substances under the Louisiana Uniform Controlled Dangerous Substances Law.
Sweden's public health agency suggested classifying clonazolam as a hazardous substance on June 1, 2015.
Clonazolam's effects are similar to other benzodiazepines, such as anxiolysis, disinhibition, lethargy, muscle relaxation, and euphoria. While no dose of clonazolam is considered "safe" due to its lack of research and extreme potency, doses higher than 0.5 mg can cause benzodiazepine overdose in some individuals. The effects of a benzodiazepine overdose include seizures, agitation, confusion, and coma.
^Laura M. Huppertz; Philippe Bisel; Folker Westphal; Florian Franz; Volker Auwärter; Bjoern Moosmann (July 2015). "Characterization of the four designer benzodiazepines clonazolam, deschloroetizolam, flubromazolam, and meclonazepam, and identification of their in vitro metabolites". Forensic Toxicology. 33 (2): 388–395. doi:10.1007/s11419-015-0277-6.
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