Rohypnol is an intermediate-acting benzodiazepine with general properties similar to those of Valium (diazepam). It is used in the short-term treatment of insomnia, as a pre-medication in surgical procedures and for inducing anaesthesia.

Like other benzodiazepines (such as Valium, Librium and Xanax), Rohypnol's effects include sedation, muscle relaxation, reduction in anxiety, and prevention of convulsions. However, Rohypnol's sedative effects are approximately 7 to 10 times stronger than Valium. The effects of Rohypnol appear 15 to 20 minutes after administration and last approximately four to six hours. Some residual effects can be found 12 hours or more after administration.

Since the 1990s Rohypnol has been used illegally to lessen the depression caused by the abuse of stimulants, such as cocaine and methamphetamine, and also as an aid for sexual assault. The so-called “date-rape drug” was placed unknowingly in the drinks of victims, often at a bar or party (“club drug”). Due to the strong amnesia produced by the drug, victims would have limited or no recollection of the assault.