New psychoactive substances: Pharmacology and impact on human health

Abstract

New Psychoactive Substances (NPS) are described by the United Nations Office for Drugs and Crime as substances of abuse, either in a pure form or a preparation, that are not controlled by the 1961 Single Convention on Narcotic Drugs or the 1971 Convention on Psychotropic Substances, but which may pose a public health threat. The term new does not necessarily refer to new inventions—several NPS were first synthesized decades ago—but to substances that have recently become available on the market. NPS are known in the market by terms such as Legal Highs, Herbal Highs, Bath Salts and Research Chemicals. The classification of psychoactive substances can be based on various criteria, including their pharmacological effects or chemical structure. The majority of new psychoactive substances are assigned to six main effect groups on the basis of their psychopharmacology: Stimulants, Synthetic opioids, Synthetic cannabinoid receptor agonists, Dissociatives, Classic hallucinogens and Sedatives/Hypnotics. The rapid evolution of NPS makes it difficult to assess their potential risks and consequences and many new psychoactive drugs have little to no scientific research or data on their pharmacology, toxicology, and potential health risks. The unknown purity and composition of specific NPS pose serious risks to users, as evidenced by emergency hospital admissions and deaths linked to NPS, often involving cases of polysubstance use. Nevertheless, the comprehension of the negative health effects and societal harms associated with NPS is limited, creating challenges in the realms of both prevention and treatment.