Current "legal highs".

BACKGROUND: A growing number of novel substances have been abused as recreational drugs by young people in the United States (US), Europe, and Australia. Called "legal highs," these substances range from plant-based to completely synthetic compounds. Spice, Salvia, mephedrone, methylenedioxypyrovalerone (MDPV), and other cathinone derivatives have psychotropic effects and are marketed for recreational use through exploitation of inadequacies in existing controlled substance laws.

OBJECTIVES: This article reviews available literature on the most common "legal highs" as well as discussing the scientific basis for the legal difficulties in controlling trafficking in these novel substances.

CONCLUSIONS: "Legal highs" continue to increase in use in the US, Europe, and Australia. These substances are powerful, can mimic effects of more traditional drugs of abuse, and are intentionally manufactured to circumvent existing controlled substance laws. As controlled substance legislation may be inadequate in the face of the quickly evolving legal highs, physicians are likely to see an increase in the prevalence of legal highs.