Drug dictionary

Glossary of terms

Cannabis social clubs (CSCs)
Private, non-profit organisations where cannabis is collectively grown and distributed to registered members, including for on-site consumption. The UN drug conventions have been interpreted as permitting CSCs, on the basis that they are an extension of decriminalisation policies.

‘Decriminalisation’ refers to the removal of criminal penalties for certain activities related to drug use — usually possession of small amounts for personal use, but sometimes minor supply or cultivation offences. In some legal systems criminal penalties are replaced by civil sanctions (such as small fines), while in other systems no penalties are applied. It is sometimes confused with legalisation, which is a distinct concept allowing for legal supply of formerly prohibited drugs.

  • De facto decriminalisation
    Where the drug-related activity remains a criminal offence, but the law is not enforced in practice. See also diversion.
  • De jure decriminalisation
    Where decriminalisation is formally established in a legal framework, through statute or constitutional court decisions.

Depressants are a category of drug defined by their effect on the central nervous system in depressing arousal and stimulation, slowing down the messages between the brain and the body (hence sometimes referred to as 'downers') - the opposite effect to stimulant drugs. They include opioids, alcohol and benzodiazepines. In lower doses they can cause a person to feel more relaxed and less inhibited, and provide relief from pain or anxiety. In higher doses they can cause drowsiness, and respiratory depression, potentially leading to unconsciousness or death.

Drug diversion schemes
‘Diversion schemes’ are police-led programmes that divert people caught committing minor offences away from the criminal justice system. Drug offence diversion schemes usually apply to the possession of illegal drugs for personal use, or sometimes to minor supply or cultivation offences. Police offer to divert people to an assessment, and/or targeted support including drug education, harm reduction or treatment, as an alternative to arrest, prosecution or caution. Diversion schemes can be pre-arrest, or post-arrest with prosecution dropped if the person complies with conditions. Some schemes also provide in-depth support to examine and address the root causes of the person’s drug use and related behaviour.

Drug checking (drug safety testing)
Drug checking allows people who have bought drugs to have samples tested to establish the content and / or strength of the product. If the test shows that the product is adulterated, or is high in strength, the individual can then make an informed decision as to whether to take the drug, or reduce their dose. In the UK, drug checking has been facilitated at festivals and city centres by organisations like The Loop. The WEDINOS service in Wales provides checking of main constituents of drugs (but not strength) sent via the post.

Drug Consumption Rooms
See ‘Overdose Prevention Centres’

Harm reduction
Harm reduction refers to policies, programmes and practices that aim to minimise negative health, social and legal impacts associated with drug use, drug policies and drug laws (Harm Reduction International). This pragmatic approach aims to make use safer, rather than simply trying to eliminate it (whether through law or abstinence). Harm reduction involves approaches such as opioid substitution therapy, overdose prevention centres, needle and syringe programmes, provision of naloxone, safer smoking kits, and the provision of information on safer drug use.

Heroin assisted treatment (HAT)
Prescribing pharmaceutical grade heroin (known as diamorphine) as part of treatment for people who inject heroin. This is a harm reduction measure designed to reduce the risks associated with using illegal heroin, and to allow access to safe medical settings. HAT is recommended as a treatment approach when more common opioid substitution therapy treatments, like the provision of methadone, prove to be ineffective. There are different models for prescribing heroin, either supervised in a clinic, or for take-home use, which we discuss in our briefing on HAT.

Legalisation is the process of ending or repealing the prohibition of a drug. The term refers to the process of legal reform, rather than the specific policies that may come after. Legalisation, therefore, means the step between prohibition and legal regulation.

Legal regulation
The establishment of formal controls over the production, supply and availability of drugs.This will generally include licensing regimes, systems of taxation, marketing regulations, health and safety requirements, quality control standards and so forth. Setting out practical models for the effective legal regulation of drugs is core to Transform’s work.

Needle and syringe programmes (NSPs)
When drugs are injected, there are additional risks — including the transmission of infection by sharing injecting equipment. NSPs supply clean needles and syringes to people who inject drugs, often in the context of other harm reduction provision such as information and support to reduce risk.

Naloxone is a medicine which can temporarily reverse the effects of an overdose caused by opioids such as heroin, methadone or fentanyl. The provision of naloxone, and training in how to administer it, is widely viewed as a key means to reducing overdose deaths.

Novel (or new) psychoactive substances (NPS)
NPS is an umbrella term used to describe a wide range of synthetic drugs often designed to replicate the effects of more established substances. Production of such drugs increased significantly from the late 2000s leading to calls for new legislation. The UK's 2016 Novel Psychoactive Substances Act addressed the issue by prohibiting the sale of all psychoactive substances not covered by the schedules of the 1971 Misuse of Drugs Act (with the exception of alcohol, nicotine and caffeine).

Opioids are a group of chemically related drugs that can induce analgesia, euphoria, and, in higher doses, drowsiness, unconsciousness, and respiratory depression or death. The term ‘opiates’ is generally used for drugs derived from the opium poppy (including heroin, morphine, codeine, hydromorphone), while ‘opioid’ is a broader term that also includes synthetic (non-naturally occurring) drugs (including methadone, buprenorphine, and fentanyl). ‘Opioid’ is therefore more commonly (and usefully) used in drug policy debates.

Opioid substitution therapy (OST)
Opioid substitution therapy, or OST, is the provision of alternative opioids (e.g. methadone or buprenorphine) to individuals who are in treatment for heroin dependence.

Overdose prevention centres (OPCs)
Sometimes called safer drug consumption rooms (DCRs) or supervised injection facilities (SIFs). OPCs are hygienic, safe spaces where high-risk drug use (such as heroin injecting, or smoking of crack cocaine) can take place under the supervision of trained staff. In an OPC, individuals have access to sterile equipment and bins for the disposal of waste, and staff can respond immediately to overdose or other medical emergencies. OPCs also provide an opportunity for brief interventions and advice, or for people to be referred to drug treatment, mental health services, wound care, blood testing and other support. See our briefing paper for more.

People who use drugs
This is a non-stigmatising alternative to ‘drug users’, and other more alienating terms often used in the media and public discourse. Rather than define individuals solely by their use of drugs, ‘people who use drugs’ focuses on the fact that those being referred to are people first and foremost. Similarly, it is preferable to refer to ‘people who inject drugs’, ‘people with drug dependencies’ and so forth. The Scottish Drug Forum have produced a very helpful guide to non-stigmatising language.

Prohibition means ‘the action of forbidding something, especially by law’. In the case of drugs, it refers to national and international laws which outlaw the production, transportation, supply, possession and (though not always) use of specified substances. Prohibition was famously implemented in relation to alcohol in the US from 1920 to 1933.

Precursors are chemicals that, while not necessarily psychoactive in themselves, are used in the production of drugs. Often, attempts to restrict the production of illegal drugs involve interventions to prevent the manufacture or transportation of precursors. Precursors were added to the UN system of controlled drugs under the 1988 UN Convention.

Psychedelics are a group of drugs defined by their effects inducing subjective changes in perception and consciousness. Examples include LSD (Lysergic Acid Diethylamide), psilocybin (naturally occurring in ‘magic mushrooms’), DMT (N-Dimethyltryptamine) and mescaline. The modern term ‘psychedelic’ is derived from the Greek words psyche and delios (literally; ‘mind manifesting’). Psychedelics are a subset of the broader drug category of ‘hallucinogens’ that also includes ketamine, nitrous oxide, and PCP.

Stimulants are a group of drugs broadly characterised by their effect of increasing activity in the central nervous system (the opposite effect to depressants). They include cocaine, methamphetamine and MDMA, and caffeine. The precise nature of these effects varies but, generally, they increase energy, alertness, and wakefulness. They usually interact with the brain’s monoamine neuro-transmitters, which include dopamine, norepinephrine, and serotonin. For more detailed information, see our 2020 publication, How to regulate stimulants: a practical guide.