New psychoactive substances and new patterns of use, though usually first appearing among restricted social groups or in a few locations, can have important implications for public health and for drug policy. Providing timely and objective information to policymakers, professionals and the wider public on new threats is methodologically and practically challenging. And it is of growing importance, given the increasingly dynamic and fast-moving nature of the European drugs problem. The European Union’s early-warning system has been developed as a rapid-response mechanism to the emergence of new psychoactive substances on the drug scene.
A large number of new unregulated synthetic compounds have appeared in recent years. These substances are marketed on the Internet as ‘legal highs’ and are designed to circumvent drug controls. They constitute a challenge to current approaches for monitoring and controlling new psychoactive substances. As reviewed in this chapter, the last two years have seen the emergence of new, smokable herbal products laced with synthetic cannabinoids and the growing popularity of various synthetic cathinones.