This self-commissioned review follows an ACMD report published in 2020, which recommended 3 benzodiazepines for control under Class C of the Misuse of Drugs Act 1971 and Schedule 1 of the Misuse of Drugs Regulations 2001. Since then, the ACMD monitoring group has become aware of the detection and non-medical use of a further group of novel benzodiazepines in the UK and Europe. Evidence was therefore sought from stakeholders concerning 18 different compounds detected in international markets to establish their prevalence in the UK. Prompted by concerns of the abuse potential of these substances, the ACMD have conducted a review to assess the available evidence on prevalence and harms of these compounds, to identify those that warrant further legislative control.

Compounds detected in Europe and the UK. p.5

A 1,4 Benzodiazepines p.7

• (#1) Gidazepam
• (#2) desalkylgidazepam
• (#3) Methylclonazepam
• (#4) Cinazepam
• (#5) Cloniprazepam
• (#6) Difludiazepam
• (#7) Thionordazepam

B Triazolobenzodiazepines p.11

• (#8) Clobromazolam
• (#9) 4'-Chloro-deschloroalprazolam

C Thienotriazolodiazepines p.13

• (#10) Fluclotizolam
• (#11) Deschloroclotizolam
• (#12) Flubrotizolam
• (#13) Fluetizolam

D Others p.14

• (#14) Bentazepam
• (#15) Tofisopam
• (#16) Bretazenil
• (#17) Rilmazafone
• (#18) Alprazolam triazolobenzophenone