The rapid emergence of a large number of NPS on the global drug market poses a significant risk to public health and a challenge to drug policy. Often, little is known about the adverse health effects and social harms of NPS, which pose a considerable challenge for prevention and treatment. The analysis and identification of a large number of chemically diverse substances present in drug markets at the same time is demanding. Monitoring, information sharing, early warning and risk awareness are essential to respond to this situation.

NPS have been known in the market by terms such as “legal highs”, “bath salts” and “research chemicals”. UNODC uses the term “new psychoactive substances (NPS)” which are defined 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.

What are the risks of NPS?

The use of NPS is often linked to health problems. In general, side effects of NPS range from seizures to agitation, aggression, acute psychosis as well as potential development of dependence. NPS users have frequently been hospitalized with severe intoxications. Safety data on toxicity and carcinogenic potential of many NPS are not available or very limited, and information on long-term adverse effects or risks are still largely unknown. Purity and composition of products containing NPS are often not known, which places users at high risk as evidenced by hospital emergency admissions and deaths associated with NPS, often including cases of poly-substance use.

Global emergence of new psychoactive substances up to November 2023:

Note: The boundaries and names shown and the designations in this document do not imply official endorsement or acceptance by the United Nations. Dashed lines represent undetermined boundaries. The dotted line represents approximately the Line of Control in Jammu and Kashmir agreed upon by India and Pakistan. The final status of Jammu and Kashmir has not yet been agreed upon by the parties. The final boundary between the Republic of Sudan and the Republic of South Sudan has not yet been determined. A dispute exists between the Governments of Argentina and the United Kingdom of Great Britain and Northern Ireland concerning sovereignty over the Falkland Islands (Malvinas).

Source: United Nations Office on Drugs and Crime, Early Warning Advisory on NPS, 2023.

How widespread are NPS?

NPS have become a global phenomenon with 141 countries and territories from all regions of the world having reported one or more NPS. Up to November 2023, 1,230 substances have been reported to the UNODC Early Warning Advisory (EWA) on NPS by Governments, laboratories and partner organisations. NPS available on the market have similar effects as substances under international control such as cannabis, cocaine, heroin, LSD, MDMA (ecstasy) or methamphetamine. Looking at the effects of synthetic NPS that have been reported until November 2023, the majority are stimulants, followed by synthetic cannabinoid receptor agonists and classic hallucinogens with a notable increase in synthetic opioids in recent years. Learn more about the various NPS effect groups on the market here.


Synthetic new psychoactive substances by effect group, up to November 2023:


Source: United Nations Office on Drugs and Crime, Early Warning Advisory on NPS, 2023.

Categories of NPS sold in the market

The main substance groups of NPS are aminoindanes (e.g. 5,6-methylenedioxy-2-aminoindane (MDAI)), synthetic cannabinoids (e.g. APINACA, JWH-018), synthetic cathinones (e.g. 4-methylethcathinone (4-MEC) and α-pyrrolidinopentiophenone (α –PVP)), phencyclidine-type substances (e.g. methoxetamine (MXE)), phenethylamines (e.g. 2C-E and 25H-NBOMe), piperazines (e.g. benzylpiperazine (BZP) and 1-(3-chlorophenyl) piperazine (mCPP)), plant-based substances (e.g. kratom (mitragyna speciosa Korth), salvia divinorum and khat (Catha edulis)), tryptamines (e.g. α-methyltryptamine (AMT)), and other substances (e.g. 1,3-dimethylamylamine (DMAA)). Learn more about the various NPS substance groups on the market here.

What is the legal situation of NPS?

Since NPS are not controlled under the International Drug Control Conventions, their legal status can differ widely from country to country. Up to 2022, 67 countries and territories have implemented legal responses to control NPS, with many having used or amended existing legislation and others having used innovative legal instruments. Several countries an territories where a large number of different NPS has rapidly emerged, have adopted controls on entire substance groups of NPS using a so-called generic approach, or have introduced analogue legislation that invokes the principal of “chemical similarity” to an already controlled substance to control substances not explicitly mentioned in the legislation. At the international level, up to March 2023, the Commission on Narcotic Drugs decided to place 78 NPS under international control. These control measures have to be implemented into the national legal framework of each country. To find more information on the various legal responses in place around the world, click here.

How is UNODC assisting Governments in this area?

To assist Member States in the identification and reporting of NPS, UNODC established the Early Warning Advisory (EWA) on NPS. The EWA serves as a repository of information on NPS leading to an improved understanding of their distribution and harm and provides a platform for the provision of technical assistance to Member States. Information in the EWA from drug seizures as well as drug identifications in biological fluid casework enables a more comprehensive overview of the NPS landscape and allows to better understand health threats posed by NPS. Information from the EWA contributes to identifying the most harmful, persistent and prevalent NPS, an important step towards prioritizing NPS for international review in the framework of the International Drug Control Conventions. To assist the work of law enforcement, forensic drug testing and toxicology laboratories, UNODC provides assistance in the areas of quality assurance, provision of manuals and guidelines, drug and precursor field detection kits and handheld devices, together with training in the UNODC laboratory in Vienna and in the field.