UK Drug Groups & Classes
This article is for general educational purposes only and does not constitute legal or medical advice. The information is correct at the time of publishing. Please refer to the published date stamp for updates. If you have concerns about drug use, please speak to a healthcare professional.
Cannabis, cocaine, ketamine, benzodiazepines, opiates, NPS … if you've ever looked into workplace drug testing, drug driving laws, or UK drugs policy, you'll have come across a confusing mix of terms. Some describe how a drug is classified under UK law, others describe how a drug affects the body, and others still describe which panel on a drug test kit will pick it up.
This guide breaks down the main drug groups and categories used in the UK, so you can better understand what's legal, what's controlled, and which type of drug test kit is right for the substances you need to screen for.
Two ways drugs are grouped in the UK
Broadly speaking, drugs in the UK are grouped in two different, but related, ways:
- Legal classification – how a substance is controlled under UK law, primarily the Misuse of Drugs Act 1971.
- Pharmacological or testing category – how a substance affects the body (stimulant, depressant, opioid, dissociative, etc.), which is how drugs are grouped on the panels of a urine or saliva drug test.
Understanding both is useful, particularly for employers who need to choose a test kit that actually covers the substances relevant to their workplace or sector.
UK legal drug classes: A, B and C
Illegal drugs in the UK are controlled under the Misuse of Drugs Act 1971, which splits substances into three classes according to the harm they're considered to pose. The maximum penalties for possession increase with the class of the drug.
| Class | Example substances | Maximum penalty for possession |
| Class A | Heroin, crack & cocaine, ecstasy (MDMA), LSD, magic mushrooms, methamphetamine, methadone | Up to 7 years' imprisonment, an unlimited fine, or both |
| Class B | Cannabis, ketamine, amphetamines, codeine, synthetic cannabinoids (e.g. Spice), synthetic cathinones (e.g. mephedrone), GHB/GBL | Up to 5 years' imprisonment, an unlimited fine, or both |
| Class C | Benzodiazepines (e.g. diazepam, temazepam), tramadol, anabolic steroids, khat | Up to 2 years' imprisonment, an unlimited fine, or both |
Classifications change over time: ketamine moved from Class C to Class B in 2014, GHB and GBL moved from Class C to Class B in 2022, and many synthetic cannabinoids were added to Class B in 2017. Substances not specifically listed can still be controlled under the Psychoactive Substances Act 2016, which introduced a general ban on producing or supplying anything sold for its psychoactive effect.
Opioids and opiates
The terms are often used interchangeably, but there's a technical difference. Opiates are naturally derived from the opium poppy (heroin, morphine, codeine), while opioids is the broader umbrella term that also includes synthetic and semi-synthetic drugs such as methadone, buprenorphine, tramadol, oxycodone and fentanyl.
Opiates and opioids remain some of the most commonly screened-for drugs on both urine and saliva panels, and in recent years testing has expanded to cover potent synthetic opioids that don't always show up on a standard opiate test.
- Fentanyl: a synthetic opioid many times stronger than morphine, increasingly found mixed into other street drugs.
- Nitazenes: a newer class of synthetic opioids, sometimes stronger than fentanyl, which standard opiate tests can miss entirely.
For a single kit that screens for opiates, fentanyl, carfentanyl, nitazenes and xylazine together (also suitable for testing powders and surfaces), we also stock a dedicated combination test:
Stimulants
Stimulants speed up the messages travelling between the brain and body. This category includes cocaine and crack cocaine (Class A), amphetamines (Class B), methamphetamine (Class A), MDMA/ecstasy (Class A), and synthetic cathinones such as mephedrone (Class B).
Stimulants feature on almost every combination drug test we sell, from our best-selling 5 panel urine drug test collection through to our more extensive multi-panel kits.
Cannabinoids
This group covers cannabis (THC), a Class B drug, as well as synthetic cannabinoids such as Spice and Mamba, which mimic the effects of cannabis but are often far more unpredictable and potent. Synthetic cannabinoids are also Class B, having been specifically added to the Misuse of Drugs Act in 2017.
Cannabis is one of the most frequently screened-for substances in workplace and home drug testing, and is included as standard on almost all of our combination panels.
Depressants: benzodiazepines, barbiturates & GHB/GBL
Depressants slow down activity in the central nervous system. Benzodiazepines (diazepam, temazepam and similar "minor tranquillisers") are generally Class C, while barbiturates and GHB/GBL sit in Class B. These substances are often taken alongside opioids, which increases the risk of overdose, so many workplace and clinical panels include a dedicated benzodiazepine test.
Benzodiazepine screening is included on many of our multi-panel kits, including the ALLTEST 12 panel saliva drug test below, and our range of ultra-sensitive saliva kits.
Dissociatives: ketamine & PCP
Dissociatives distort perception of sight, sound and one's sense of self. Ketamine is a Class B drug in the UK (reclassified from Class C in 2014), while PCP is Class A. Ketamine misuse has been rising in recent years, and it isn't always included on older or more basic drug test panels.
If ketamine is a specific concern, we stock a standalone ketamine saliva test kit:
New psychoactive substances & synthetic opioids
New psychoactive substances, once sold as "legal highs," are now covered by a general ban under the Psychoactive Substances Act 2016, even where a specific chemical hasn't yet been individually added to the Misuse of Drugs Act. This category includes synthetic cannabinoids, synthetic cathinones, and the emerging group of synthetic opioids such as nitazenes, which have become a significant public health concern across the UK.
Because NPS chemistry changes quickly, standard drug test panels can't always keep up, which is why the specialist nitazene and synthetic opioid kits above exist alongside our broader multi-panel tests.
Matching drug categories to the right test panel
Drug test kits are usually described by the number of drugs they screen for – a "5 panel," "10 panel," "12 panel," or "13 panel" test – with each additional panel covering a different drug group.
| Panel size | Typical drug groups covered |
| 5 panel | Cannabis, cocaine, opiates, amphetamines, benzodiazepines (or methamphetamine) |
| 10 panel | The above plus methamphetamine, MDMA, ketamine, synthetic cannabinoids (K2) & cotinine (nicotine) |
| 12 panel | Core groups plus ketamine, tramadol, oxycodone & fentanyl |
| 13 panel | Core groups plus buprenorphine, barbiturates, PCP & tricyclic antidepressants |
An example of a well-rounded 10 panel urine kit, popular with schools, workplaces and parents:
And for the widest single-cup coverage, our 13 panel ultra sensitive urine test cup:
Our full range of integrated cup drug test kits and oral fluid drug tests lets you choose the panel that best matches the drug groups relevant to your situation.
Why understanding drug categories matters
Choosing the right test isn't just about picking the biggest panel available. A construction site might prioritise cannabis, cocaine and ketamine; a healthcare setting might need strong opioid and benzodiazepine coverage; a school or family setting may want a broader, more sensitive combination panel. Understanding the drug groups behind the numbers helps you choose a test kit that's actually fit for purpose, rather than one that simply lists the most drugs.
Our quick guide to drug testing kits and our article on which drugs don't show up on a standard test are good next steps if you're still deciding which kit is right for you.
Does a drug's legal class reflect its risk to employers?
Not reliably. The A/B/C system reflects how harmful the Advisory Council on the Misuse of Drugs judges a substance to be to the individual and to society, factoring in things like addiction potential, physical harm and the wider social cost of use. It says nothing about how common a drug is, how easily it's obtained, or how likely it is to affect someone at work.
Cannabis, a Class B drug, is consistently the most frequently detected substance in UK workplace testing simply because it's widely used and stays detectable in urine for far longer than most other drugs. Cocaine, by contrast, is Class A yet turns up regularly in sectors like hospitality, finance and construction, where its short detection window means it's often under-represented in testing data despite genuinely high usage. Benzodiazepines sit in the lowest tier, Class C, but remain a serious workplace concern because of how impairing they are and how often they're misused alongside other substances such as opioids.
The takeaway for employers: the drug groups worth prioritising in a workplace testing policy are the ones prevalent in your sector and workforce, not simply the ones carrying the heaviest criminal penalty. A workplace drug test kit chosen to reflect your actual risk profile will always outperform one chosen on legal severity alone.
The information in this article is provided for general educational purposes only and does not constitute legal or medical advice. Drug classifications under the Misuse of Drugs Act 1971 and the Psychoactive Substances Act 2016 can and do change over time; always check current UK legislation or seek professional legal advice if you need up-to-date, definitive guidance.
Point-of-care drug test kits are screening tests only. Any non-negative result should be confirmed using an accredited laboratory confirmation method before any decisions or actions are taken based on the result.
If you have concerns about your own or someone else's drug use, please speak to a healthcare professional or a dedicated drug and alcohol support service.