New psychoactive substances. An actual problem or an overestimated phenomenon?

In last years, international and national Institutions have been completely focused on the new psychoactive substances (NPS) phenomenon. Many contrast policies have been planned in order to control their spread. Even scientific entities, such as our Forensic Toxicology Division, have spent time and resources for NPS identification in biological (from clinical and forensic caseworks) and non-biological (seized material) samples. Last reports show a low prevalence of NPS across the Europe and Italy, while the classical drugs are still the main cause of drug-related deaths. In particular, a worrisome datum is represented by the increasing number of deaths due to heroin. Seen these statistics, is the NPS phenomenon overestimated? Is the interest in classical drugs decreased? Were we diverted by NPS?