What is drug checking?

Drug checking services aim to reduce drug related harms by allowing people to get substances of concern tested for content and sometimes also potency - and receive tailored harm reduction advice alongside the test results.

This service enables people who use drugs to make more informed decisions, avoid unwanted drugs or adulterants, and reduce risks of accidental overdose or other adverse events. The service generally involves people voluntarily dropping off a numbered sample into an amnesty bin, without fear of arrest or legal sanction. The sample can then be subject to a range of forensic testing, and the results delivered as part of a harm reduction advice package, tailored to the test results and individual circumstances. None of the drug sample is returned to the person who dropped it off, with any excess not needed for testing destroyed.

A range of different types of drug checking models exist, catering for a range of needs in different environments - from comparatively low-tech informal pop-up services, to more sophisticated mobile or static laboratory-based provision, along with combinations of rapid lower tech and lab testing in many services. Drug checking has been used for music festivals and events, as well as in urban centres - catering for people who use drugs in the night time economy, and people who use drugs problematically (in other countries, sometimes as part of other services such as overdose prevention centres (OPC)).

Drug testing services at a UK festival

Inside a Copenhagen Overdose Prevention Centre

Techniques used to test drugs (often used in parallel) range from colorimetric reagent testing and fentanyl test-strips, through to database linked infrared spectroscopy (FTIR), and gas chromatography (GCMS).

Photo credit: The Loop. Testing with FTIR

What are the benefits of drug checking?

All drug use carries some degree of risk, but illegal production and supply of drugs increases these risks. Unknown and unpredictable potency, mis-selling and adulteration of illegal drugs all increase risks of health emergencies or deaths related to drug use. Testing and provision of related harm reduction information can reduce these risks and encourage safer drug using behaviours amongst those who get their drugs tested, and their peers.

Testing services can also:

  • Provide information to those dealing with drug-related incidents or emergencies, so that medical and welfare services can provide prompt, informed and targeted treatment.
  • Link harm reduction advice directly with analysis of drugs currently in circulation in local drug markets, which research shows to be more effective.
  • Access hidden and hard-to-reach populations who otherwise do not engage with existing drug services - notably young people and novice users at greater risk (with UK research by Measham and colleagues showing these groups being disproportionately more likely to take up opportunities to use drug checking services in the UK)
  • Provide information that can be distributed via social media, early warning systems and other channels relating to particular drugs to reduce drug-related harm and to minimise the possibility of a major public safety incident.
  • Help identify trends in illegal drug markets and drug use - that can be used to tailor information and service provision relating to specific risk behaviours or populations.
Social media drug advisory from the Loop

Where is drug checking happening?

Drug checking services operate in a growing number of countries including Austria, Australia, Belgium, Canada, Colombia, Mexico, the Netherlands, Portugal, Spain, Switzerland, the United States and the UK. All are free and anonymous.

  • In the UK, drug checking services were piloted by The Loop (a non-profit dedicated drug checking NGO) at two festivals in 2016, before being rolled out more widely at UK events. The Loop has also since established the UK’s first Home Office licensed regular city centre drug checking in Bristol, following the first city centre pilots in Bristol and Durham in 2018.
  • In Swiss cities like Bern and Zurich, people can drop off samples for testing midweek at a city centre location and get the results back by Friday. They phone a drug counsellor who provides harm reduction advice alongside details of test results.
  • The Netherlands has a long established national drug checking service, offering testing at over 20 city centres drop off points, with results usually within 1-2 days. Most samples are tested using FTIR and reagents with a small subsample being sent to a commercial lab for subsequent verification.
  • Austria’s ‘Checkit’ project has a mobile facility providing on-site testing at music events throughout the year.
  • Toronto in Canada offers drug testing (including of used equipment) from 5 separate supervised drug consumption facilities (overdose prevention centres) - offering results (including from state of the art GCMS technology) within one working day.

What is the evidence for drug checking?

While it can be difficult to generalise about a wide range of services and practices around the world, we know from more sophisticated and carefully evaluated event-based services, provided by Measham and colleagues in the UK based on The Loop’s work, drug checking can lead to lowered drug use, lowered polydrug use, and have a lasting, positive health impact on service users:

  • When service users are informed that their substance of concern contains something other than what they expected, nearly two-thirds dispose of it.
  • When people are informed that their drugs are higher strength than they expected, half either take less or do not consume the substance at all.
  • Polydrug use is a known cause of drug related harm. The Loop's drug checking service can alert service users to particularly high risk drug combinations. This leads to an immediate outcome of nearly half of service users being more careful about combining drugs after receiving a Loop health consultation. Crucially, these risk reduction behaviours persist - 3 months later nearly one-third of The Loop’s drug checking service users were still being more careful about polydrug use and were still taking smaller doses than previously.

What about home testing kits?

Widely available reagent-based home testing kits can help identify the presence of certain drugs (when the liquid drops turn a certain colour), such as MDMA, to inform drug taking decisions. It is important, however, to acknowledge the limitations of these tests; they give little indication of potency and are also ineffective at identifying many drugs or adulterants. They can be a useful vehicle for harm reduction education - but are not a substitute for more sophisticated testing techniques (that can identify a wide range of drugs, potencies etc).

The Loop

Trans European Drug Information

EMCDDA drug testing hub


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