Desmethylflunitrazepam
Desmethylflunitrazepam is a benzodiazepine that occurs naturally as a metabolite of flunitrazepam1 and has been distributed as a designer drug and research chemical.12 It acts on the GABAA receptor, producing sedative, anxiolytic, and muscle relaxant effects typical of its class.1 As an understudied research chemical derived from a notably potent parent compound, its safety profile and long-term risks remain poorly characterized.1
Contents
Dosage & Duration
Dosage
Duration
Subjective Effects
Desmethylflunitrazepam produces a classic benzodiazepine experience dominated by heavy sedation, anxiety relief, and physical relaxation, consistent with its role as an active metabolite of flunitrazepam. Little formal documentation of its subjective character exists, as it has circulated primarily as a designer benzodiazepine sold online. Memory of the period following ingestion is often unreliable at moderate to high doses.
Physical
Pronounced sedation and muscle relaxation give the body a heavy, tranquil feeling that can progress into sleep at higher doses.
Sedation
Cognitive
The headspace is one of dulled, slowed thought and reduced anxiety, with anterograde amnesia becoming increasingly prominent as the dose rises.
Suppressions
Reagent Testing
Loading reagent data
Pharmacology
Pharmacodynamics
Desmethylflunitrazepam is a benzodiazepine that acts as a positive allosteric modulator at the GABA-A receptor1, where it displays high affinity with an IC50 of 1.499 nM. It is also a metabolite of flunitrazepam.13
Pharmacokinetics
Dangerous
Highest riskThese combinations are considered extremely harmful and should always be avoided. Reactions to these drugs taken in combination are highly unpredictable and have a potential to cause death.
Unsafe
AvoidThere is considerable risk of physical harm when taking these combinations, they should be avoided where possible.
Caution
Use cautionThese combinations are not usually physically harmful, but may produce undesirable effects, such as physical discomfort or overstimulation. Extreme use may cause physical health issues. Synergistic effects may be unpredictable. Care should be taken when choosing to use this combination.
Tolerance
Benzodiazepines, GABAergic depressants
Harm Potential
Addiction & Dependence
Psychological
Classified as habit-forming, indicating potential for psychological dependence.1
History & Culture
Desmethylflunitrazepam was originally identified as an active metabolite of flunitrazepam14, the potent benzodiazepine marketed under trade names such as Rohypnol5. The compound has since emerged on the grey market as a designer drug, sold online as a research chemical under names including fonazepam and the research designation Ro05-443512.
Legality
References
Source Pages
Citations
- (2016). Metabolites replace the parent drug in the drug arena. The cases of fonazepam and nifoxipam. Forensic Toxicology, 35(1), 1–10. https://doi.org/10.1007/s11419-016-0338-5123456789
- (November 2016). Characterization and in vitro phase I microsomal metabolism of designer benzodiazepines - an update comprising adinazolam, cloniprazepam, fonazepam, 3-hydroxyphenazepam, metizolam and nitrazolam. Journal of Mass Spectrometry, 51(11), 1080–1089. https://doi.org/10.1002/jms.384012
- (April 2001). Flunitrazepam metabolism by cytochrome P450S 2C19 and 3A4. Drug Metabolism and Disposition, 29(4 Pt 1), 460–5. http://dmd.aspetjournals.org/content/29/4/460.long1
- (November 1998). Quantification of flunitrazepam's oxidative metabolites, 3-hydroxyflunitrazepam and desmethylflunitrazepam, in hepatic microsomal incubations by high-performance liquid chromatography. Journal of Chromatography. B, Biomedical Sciences and Applications, 719(1–2), 87–92. https://doi.org/10.1016/s0378-4347(98)00383-11
- (2016). Rohypnol® (Flunitrazepam) — Facing Addiction in America. Facing Addiction in America: The Surgeon General's Report on Alcohol, Drugs, and Health. https://www.ncbi.nlm.nih.gov/books/NBK424847/table/appd.t18/1
Further Reading
Automated synthesisInformation aggregated and synthesized using an autonomous workflow built by Josie Kins.
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