Meclonazepam Stats & Data
NPS DataHub
MW329.74
FormulaC16H12ClN3O3
CAS58662-84-3
IUPAC(3S)-5-(2-chlorophenyl)-3-methyl-7-nitro-1,3-dihydro-1,4-benzodiazepin-2-one
SMILES
O=N(=O)c1ccc2NC(=O)C(C)N=C(c3ccccc3Cl)c2c1InChIKey
LMUVYJCAFWGNSY-VIFPVBQESA-N
Chemical Class
Benzodiazepine
Psychoactive Class
Depressant
History & Culture
Meclonazepam was first synthesized by a research team at Hoffmann-La Roche during the 1970s as a benzodiazepine derivative structurally related to clonazepam. Early investigations identified potential anti-parasitic applications against Schistosoma mansoni, the parasitic flatworm responsible for schistosomiasis, though this therapeutic avenue was never developed to the point of clinical approval. The compound was never marketed as a pharmaceutical product. It later emerged on the grey market as a designer drug, though it has not achieved widespread popularity within recreational drug communities.
Effect Profile
Curated + 1 Reports
Benzodiazepine
6.6
Strong euphoria and anxiolysis with mild cognitive impairment, low sedation
Anxiolysis×3
8
Sedation / Relaxation×2
3
Motor / Cognitive Impairment×1
4
Euphoria / Mood Lift×1
10
Based on reports from:
Tolerance & Pharmacokinetics
drugs.wikiTolerance Decay
Full tolerance
3d
Half tolerance
37d
Baseline
~60d
Experience Report Analysis
Erowid
1
Reports
2022–2022
Date Range
1
With Age Data