Michelle Muscat MD MRCS(Ed) MSc, PG Dip, FRCPath, PhD

Flunitrazepam or ‘rohypnol’ is best known as a date rape drug or “roofie”(1). It is a benzodiazepine with strong sedative and hypnotic effects. It is also associated with amnesic effects (2), sleep alterations (3) and has been used in the treatment of insomnia. Paradoxical effects such as confusion, agitation and aggression have also been reported, together with risky decision making (4-6). In the past the drug had been used for anaesthetic purposes (7, 8)

Its use in the facilitation of sexual assault makes both its clinical and forensic toxicological profiles extremely pertinent (9, 10). Some instances have been associated with leaving an unattended drink. The concerns led even to the trials of portable Raman spectrometers to detect spiked drinks (11) in addition  to existing and emerging laboratory confirmation methods (12-15). Fluorescence spectroscopy has also been proposed to screen colourless drinks (16). Flunitrazepam has been associated with medicolegal cases (17) and even forensic psychiatry in relation to dangerous activities, crime propensity (18) and criminal lifestyle associations (19) of the drug.

Other reported effects include skin necrosis (20). A recent case report described gastric fluid that was bright blue after flunitrazepam overdose (21). A case report described intra-arterial injection of flunitrazepam together with methadone, water and saliva resulting in compartment syndrome (22). Fluctuations in blood pressure between night-time and morning have been documented with chronic flunitrazepam use (23). These are some illustrative examples, other instances were reported of other effects alone or in combination with other drugs.



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