Monitoring new psychoactive substances (NPS) in The Netherlands: data from the drug market and the Poisons Information Centre

Abstract

BACKGROUND: In recent years, the number of new psychoactive substances (NPS) appearing on the illicit drug market strongly increased. However, little is known about their toxic effects and risks. Therefore, we determined the most frequently occurring NPS in The Netherlands and combined this with data regarding drug-related intoxications. METHODS: Data from the Drugs Information and Monitoring System (DIMS) and the Dutch Poisons Information Centre (DPIC) were combined and jointly analyzed. RESULTS: The number of drug samples submitted to DIMS for analysis containing NPS increased from 22 in 2007 to 431 samples in 2013. The most frequently submitted NPS in 2013 included 4-bromo-2,5-dimethoxyphenethylamine (2C-B), 4-fluoroamphetamine (4-FA), methoxetamine (MXE) and 6-(2-aminopropyl)benzofuran (6-APB). From 2012 onwards, the number of NPS bought as drug of choice exceeded those appearing as adulterants in established drugs. The DPIC was consulted about 35 NPS exposures in 2013, most frequently involving 4-FA, mephedrone, MXE, 2C-B and 6-APB. Following NPS exposure, neurological and psychological symptoms were most frequently reported, like agitation and hallucinations. In addition, cardiovascular symptoms like hypertension and tachycardia often occurred. CONCLUSIONS: NPS are currently being purchased as drug of choice in The Netherlands and their availability and use is increasing. Although pharmacological and toxicological data are scarce, NPS can induce pronounced clinical effects. Therefore, the monitoring of trends in NPS prevalence needs to be continued, combined with reported clinical effects, and preferably supported by analytical confirmation of exposures in such patients.