Meclonazepam

Meclonazepam ((S)-3-methylclonazepam) was discovered by a team at Hoffmann-La Roche in the 1970s and is a drug which is a benzodiazepine derivative similar in structure to clonazepam. It has sedative and anxiolytic actions like those of other benzodiazepines, and also has anti-parasitic effects against the parasitic worm Schistosoma mansoni.

Meclonazepam was never used as medicine and instead appeared online as a designer drug.

United Kingdom
In the UK, meclonazepam has been classified as a Class C drug by the May 2017 amendment to The Misuse of Drugs Act 1971 along with several other designer benzodiazepine drugs.