For Anthony Davies, heroin was no longer enough. Some days, the heroin he would get his hands on wouldn’t be of a very good quality. Other days, he just wouldn’t have enough money to get it. That’s when Valium became a big part of his life. Used to treat anxiety, Valium is a prescription drug which is the brand name for Diazepam. It is a type of benzodiazepine or, as they are known on the streets, ‘benzos’.