Men have long used alcohol to reduce women’s sexual inhibitions, thereby making them more willing sexual partners. If the alcohol consumption has been sufficient to render the woman incapacitated, she is vulnerable to sexual assault, including rape. Most drug-related sexual assaults are of this kind. However, in recent years, an insidious phenomenon has emerged in which a sedating drug is put clandestinely in a woman’s drink so that she isn’t even aware that anything is amiss until she wakes up hours later in the man’s bed. Drugs are sometimes used in this way on a date, hence the term “date rape” drugs. However, there have also been instances in which a woman was sexually assaulted by a total stranger after being given one of these substances. For this reason, researchers in this area prefer to use the term drug-facilitated sexual assault.

A number of different drugs have been used to assist in a sexual assault (see Schwartz et al., 2000), but besides alcohol, we will focus here on two compounds: GHB and a benzodiazepine called flunitrazepam (trade name Rohypnol). As we have seen, GHB is a CNS depressant that can induce unconsciousness in sufficiently high doses. It is colorless and odorless, which facilitates its surreptitious use by the perpetrator (although the sodium salt of GHB has a distinctive salty flavor that could be detected unless the woman’s beverage is already strongly flavored by fruit juice, for example). Its depressant effects add to those produced by alcohol, thereby increasing the likelihood that the victim will lapse into an unconscious state. Rohypnol is a powerful sleep-inducing agent that is used medicinally in numerous countries but is not currently approved for sale in the United States. Nevertheless, it is readily available illicitly under street names like “roofies,” “rophies,” or “roche” (the drug is manufactured by the Hoffmann-La Roche pharmaceutical company). Besides inducing sleep, Rohypnol may also cause anterograde amnesia, which means a lack of memory for events that occur while the recipient is under the influence of the drug. This can make it more difficult for prosecutors to prove a rape charge when Rohypnol is involved.

It is impossible to know how frequently drugs are used to perpetrate a sexual assault, partly because many assaulted women do not come forward for personal reasons, and partly because some of these compounds (e.g., GHB) are metabolized and cleared from the body relatively quickly. The incidence of GHB-facilitated sexual assaults appears to vary by country. Studies performed in the United States found the presence of GHB in about 3% to 4% of all reported sexual assault cases (Németh et al., 2010), whereas studies conducted specifically on drug-facilitated sexual assaults in the United Kingdom and in Paris found GHB in 8% of Parisian cases but in less than 1% of cases in the United Kingdom (Olszewski, 2009). A recent global review on which substances were detected in studies of drug-facilitated sexual assault found that alcohol is involved much more often than illicit drugs in the perpetration of sexual assaults (Anderson et al., 2017).

The private sector has taken several steps to improve the detectability of potential date rape drugs by women. For example, Hoffmann-La Roche replaced its old Rohypnol formulation, which was colorless when dissolved in an alcoholic beverage, with a new tablet that turns blue when dissolved. Another commercial approach to preventing drug-facilitated sexual assault is the marketing of inexpensive devices to test one’s drink for the presence of certain illicit drugs. For example, a firm called Drink Safe Technologies offers both coasters and test strips designed to detect both GHB and ketamine, which has also been used as a date rape drug. The kits do not test for flunitrazepam (Rohypnol); Drink Safe Technologies has stated that they omitted this test because the current incidence of flunitrazepam-related date rapes is low compared with the incidence of date rapes in which the victim is drugged with GHB or ketamine. As shown in Figure 1, each Drink Safe coaster contains two pairs of test circles located at the bottom corners. If the coaster is being distributed by a bar or club, it may also include some type of advertisement or logo that has been selected by the proprietor of the establishment. The woman is instructed to place a drop of her drink on both of the circles in a pair of test circles and wait for about 1 minute. A positive test is indicated by either circle turning a darker blue color, which is interpreted as a drug-contaminated drink. It is important to note that the use of the Drink Safe coaster is not recommended for highly acidic beverages such as drinks containing large amounts of fruit juice. There are other limitations as well. The color change could be masked by the drink itself (e.g., red wine), or the bar or club could be so dark that confirming a modest color change would be difficult. These limitations have been noted not only by the manufacturer but also by researchers who performed controlled, independently conducted tests of the Drink Safe coaster (Meyers and Almirall, 2004; Quest and Horsley, 2007). Therefore, even though test coasters may help prevent some sexual assaults, women should remain alert for potential adulteration of their drinks even when such coasters are available and seem to indicate that everything is normal.

Figure 1 The drink-testing coaster from Drink Safe. (Courtesy of David McIntyre.)

References

Anderson, L. J., Flynn, A., and Pilgrim, J. L. (2017). A global epidemiological perspective on the toxicology of drug-facilitated sexual assault: A systematic review. J. Forensic Legal Med., 47, 46–54.

Meyers, J. E., and Almirall, J. R. (2004). A study of the effectiveness of commercially available drink test coasters for the detection of “date rape” drugs in beverages. J. Anal. Toxicol., 28, 685–688.

Németh, Z., Kun, B., and Demetrovics, Z. (2010). The involvement of gamma-hydroxybutyrate in reported sexual assaults: A systematic review. J. Psychopharmacol., 24, 1281–1287.

Olszewski, D. (2009). Sexual assaults facilitated by drugs or alcohol. Drugs: Educ. Prev. Policy, 16, 39–52.

Quest, D. W., and Horsley, J. (2007). Field-test of a date-rape drug detection device. J. Anal. Toxicol., 31, 354–357.