Flunitrazepam (also referred by its brand name Rohypnol) is an intermediate acting benzodiazepine.
Flunitrazepam was first developed by a team led by Leo Sternbach at Hoffman La-Roche in 1963. It was first synthesized in 1972 in Europe, then entered the commercial market three years later. A series of tests demonstrated its potency for hypnotic effects, and as a result, it was used as a regular hypnotic. Its prescriptions were intended for short-term treatment for chronic or severe insomniacs who would not to other hypnotics. Because of its hypnotic potency, flunitrazepam is considered to be one of the most effective benzodiazepine hypnotics in terms of its dosage.
It is also infamous for its status as a date rape drug due to its high potency and ability to cause strong amnesia. However, a study conducted in the 1990s concluded that flunitrazepam was used in only around 1% of reported date rapes. It is also used as a recreational drug, being detected frequently alongside other sedative hypnotic drugs used by people who drive under the influence of drugs. In Sweden, flunitrazepam was the second-most used drug in suicides by drug overdose, with 16% of such cases being attributed to the drug.
Adverse effects to using flunitrazepam include dependence, both physical and psychological, leading to addiction; reduced sleep quality resulting in somnolence; and eventual overdose, which results in excessive sedation, impairment of balance and speech, respiratory depression or coma, and possibly even death. When used during pregnancy, it might also cause hypotonia. Abrupt discontinuation of flunitrazepam may cause a rebound effect that occurs after four days. It can also impair cognitive and psychomotor functions. The former results in a lack of concentration, confusion, and anterograde amnesia; while the latter results in affected reaction time, driving skill, coordination, balance, and dizziness.
Edward Hill ("Poison") used Rohypnol, combined with LSD, in his first act of mass poisoning, having his accomplice lace the candy and envelopes of a bank with it. Jerry Tidwell ("Beyond Borders") incapacitated his victims with Rohypnol, which wasn't detected by autopsies because their metabolisms broke it down easily and quickly.