Drugs (oud)

Drug use, the health and social consequences of drug use, and drug markets are constantly changing. The Trimbos Institute tracks these changes closely through various monitoring systems and research programs. This work contributes to the prevention of drug use and the reduction of drug-related problems by developing, implementing, and sharing knowledge and expertise with healthcare professionals and the general public. In addition, experts from Trimbos offer governments and policymakers the data they need to develop informed drug strategies.

Monitoring drug use and drug markets

The Trimbos Institute conducts extensive monitoring activities to better understand drug use and markets in the Netherlands. This monitoring includes knowledge synthesis from existing data sources, continuous data collection on drug use, markets, and incidents, and ad-hoc research.

Selected monitoring studies

  • A synthesis of current facts and figures on the use of drugs, alcohol, and tobacco and their consequences is reported annually in the National Drug Monitor. Operating as the National Focal Point, this information is shared with the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA).
  • The illicit drug market is monitored through long-standing monitoring systems that jointly observe trends and warn about potential public health risks. This monitoring comes through the Drug Information and Monitoring System (DIMS), which analyzes nightlife drug composition. DIMS observes online drug markets and fora and collaborates with justice and customs in the Monitor New Drugs. Other monitoring happens through the THC-monitor, which assesses the strength of cannabis products sold in Dutch cannabis coffee shops.
  • The Monitor Drug-related Incidents collects information on presentations with drug-related acute toxicities at four medical services and in eight regions of the Netherlands to provide an indicative base for monitoring. 
  • The Dutch National School Survey  is a national research effort regarding the use of tobacco, alcohol, drugs, and the internet among adolescents.
  • The European School Survey Project on Alcohol and Other Drugs (ESPAD) is a collaborative effort of independent research teams in more than forty European countries and the largest cross-national research project on adolescent substance use in the world.
  • The Health Behavior in School-aged Children (HBSC) survey collects data every four years on 11-, 13- and 15-year-old boys' and girls' health and well-being, social environments, and health behaviors. HBSC includes 44 countries and regions across Europe and North America.
  • CanDep investigates the dynamics of cannabis use and dependence in a longitudinal cohort study of young adults who frequently use cannabis.

International Drug Policy and Evaluation

The Dutch experience in prevention, harm reduction and drug policy evaluation is put to use in Trimbos’ international consultancy, assisting countries across the globe in the implementation and evaluation of national drug policies, prevention, and harm reduction activities.

Drug education and prevention

The Trimbos Institute provides clear, evidence-based information on drugs to the Dutch population and professionals.

  • the Drugs Infoline, a telephone support and information service;
  • the Drugs Infoline website, which contains information about drug use;
  • Healthy Schools:a school-based drug prevention program with specific programs for primary schools, secondary schools, and vocational schools; and
  • the Your child and club drugs website for parents, which includes a three minute (Dutch-language) video for parents about XTC. The  video can be seen here.


Jeroen  Lammers

Jeroen Lammers

Alcohol and drug use in nightlife settings

The Trimbos institute supports national and local governments in their alcohol, drugs, and tobacco policies, especially regarding nightlife settings. Trimbos provides:

  • educational materials informing partygoers about the risks of alcohol and drug use, including the Dutch-language website Drugs and Going Out;
  • training sessions to educate security and hospitality personnel about alcohol and drugs;
  • insight into policy decisions and research on key issues; and
  • tailored interventions for specific populations.


Ferry  Goossens

Ferry Goossens

Drugs and vulnerable groups

The Trimbos Institute supports research and programs about drug use and vulnerable populations. This support includes:


Staff from the Trimbos Institution author or co-author nearly 200 publications a year. These range from peer-reviewed articles in distinguished Dutch and international journals to research reports and doctoral theses. Some of these articles and reports are listed below.

Potency trends of Δ9-tetrahydrocannabinol, cannabidiol and cannabinol in cannabis in the Netherlands: 2005-15. Niesink RJ, Rigter S, Koeter MW, Brunt TM. Addiction. 2015 Dec;110(12):1941-50. doi: 10.1111/add.13082. Epub 2015 Sep 18.

Sizing the cannabis market: a demand-side and user-specific approach in seven European countries. van Laar M, Frijns T, Trautmann F, Lombi L.  Curr Drug Abuse Rev. 2013 Jun;6(2):152-64

Further insights into aspects of the illicit EU drugs market.Editors: Franz Trautmann, Beau Kilmer and Paul Turnbull. ISBN 978-92-79-29287-3 / doi: 10.2838/92919

Cross-sectional and prospective relation of cannabis potency, dosing and smoking behaviour with cannabis dependence: an ecological study. van der Pol P, Liebregts N, Brunt T, van Amsterdam J, de Graaf R, Korf DJ, van den Brink W, van Laar M. Addiction. 2014 Jul;109(7):1101-9. doi: 10.1111/add.12508. Epub 2014 Mar 17.

The Drug Information and Monitoring System (DIMS) in the Netherlands: implementation, results, and international comparison. Brunt TM, Niesink RJ. Drug Test Anal. 2011 Sep;3(9):621-34. doi: 10.1002/dta.323. Epub 2011 Sep 6. Review.

Linking the pharmacological content of ecstasy tablets to the subjective experiences of drug users. Brunt TM, Koeter MW, Niesink RJ, van den Brink W. Psychopharmacology (Berl). 2012 Apr;220(4):751-62. doi: 10.1007/s00213-011-2529-4. Epub 2011 Oct 13.

4-Fluoroamphetamine in the Netherlands: more than a one-night stand. Linsen F, Koning RP, van Laar M, Niesink RJ, Koeter MW, Brunt TM. Addiction. 2015 Jul;110(7):1138-43. doi: 10.1111/add.12932. Epub 2015 May 19.

School-based programmes to reduce and prevent substance use in different age groups: What works for whom? Systematic review and meta-regression analysis. Onrust SA, Otten R, Lammers J, Smit F. Clin Psychol Rev. 2016 Mar;44:45-59. doi: 10.1016/j.cpr.2015.11.002. Epub 2015 Dec 15. Review.

Drunk and disorganised: relationships between bar characteristics and customer intoxication in European drinking environments. Hughes K, Quigg Z, Bellis MA, Calafat A, van Hasselt N, Kosir M, Voorham L, Goossens FX, Duch M, Juan M. Int J Environ Res Public Health. 2012 Nov 12;9(11):4068-82. doi: 10.3390/ijerph9114068.

A randomized controlled trial of a brief motivational enhancement for non-treatment-seeking adolescent cannabis users. de Gee EA, Verdurmen JE, Bransen E, de Jonge JM, Schippers GM. J Subst Abuse Treat. 2014 Sep;47(3):181-8. doi: 10.1016/j.jsat.2014.05.001. Epub 2014 May 17.

Brunt, T.M., Nagy, C., Bücheli, A., Martins, D., Ugarte, M., Beduwe, C., & Ventura Vilamala, M. (2016). Drug testing in Europe: Monitoring results of the Trans European Drug Information (TEDI) project. Drug Testing and Analysis(2). doi:10.1002/dta.1954

Litjens RP, Brunt TM. How toxic is ibogaine? Clin Toxicol (Phila). 2016: 54(4): 297-302.

Hondebrink L, Nugteren-van Lonkhuyzen JJ, Van Der Gouwe D, Brunt TM. Monitoring new psychoactive substances (NPS) in The Netherlands: data from the drug market and the Poisons Information Centre. Drug Alcohol Depend. 2015: 147: 109-115.

van Amsterdam J, Brunt T, van den Brink W. The adverse health effects of synthetic cannabinoids with emphasis on psychosis-like effects. J Psychopharmacol. 2015: 29: 254-263.

Niesink RJ, Rigter S, Koeter MW, Brunt TM. Potency trends of Δ(9) -tetrahydrocannabinol, cannabidiol and cannabinol in cannabis in the Netherlands: 2005-15. Addiction. 2015: 110: 1941-1950.

Linsen F, Koning RP, van Laar M, Niesink RJ, Koeter MW, Brunt TM. 4-Fluoroamphetamine in the Netherlands: more than a one-night stand. Addiction. 2015: 110: 1138-1143.

Litjens R.P., Brunt T.M., Alderliefste G.J., Westerink R.H. Hallucinogen persisting perception disorder and the serotonergic system: A comprehensive review including new MDMA-related clinical cases. Eur. Neuropsychopharmacol. 2014: 24, 1309-1323.

Brunt TM, van Genugten M, Höner-Snoeken K, van de Velde MJ, Niesink RJ. Therapeutic satisfaction and subjective effects of different strains of pharmaceutical-grade cannabis. J. Clin. Psychopharmacol. 2014: 34, 344-9.

van Amsterdam J, Brunt T, Pennings E, van den Brink W. Risk assessment of GBL as a substitute for the illicit drug GHB in the Netherlands. A comparison of the risks of GBL versus GHB. Regul. Toxicol. Pharmacol. 2014: 70, 507-13.