An unusual detection of 2-amino-3-(2-chlorobenzoyl)-5-ethylthiophene and 2-methylamino-5-chlorobenzophenone in illicit yellow etizolam tablets marked "5617" seized in the Republic of Ireland.

Benzodiazepines are a class of compounds used clinically to treat a variety of conditions including anxiety and insomnia. Their potential for abuse has led to a surge in their availability on the illegal drugs market. End users often rely on markings on illicit tablets to identify their contents.