What are the drug classifications in the UK?

Liz Wood Alphabiolabs

By Liz Wood, Health Testing Specialist at at AlphaBiolabs
Last reviewed: 16/11/2023

In this article, we discuss the different drug classifications in the UK, which drugs belong to which classification, penalties for possession or supply of drugs, and where you can get a drug test.

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What are the drug classifications in the UK?

Drug classifications exist to divide illegal and some legal drugs into ‘classes’ depending on the level of harm that is attributed to the drug. There are three main classes of drugs: class A, B and C, and one temporary class.

Class A drugs are considered to be the most harmful. They include drugs like heroin and cocaine. Class B drugs include cannabis and ketamine. Class C drugs are considered the least harmful, and include drugs such as anabolic steroids and, as of November 2023, nitrous oxide (laughing gas).

You’ll also find some prescription medications listed as controlled drugs. Examples of these are opioid pain relief (e.g. methadone, morphine), anti-depressants, anti-anxiety and anti-epileptics. Controlled prescription drugs are only legal to possess if you have a valid prescription.

Both the harm that a drug causes to the health of an individual and the harm caused to society are considered when deciding what class a drug should belong to.

There are many different short- and long-term health effects associated with taking drugs. Class A drugs are associated with the most serious health complications compared to class B and C drugs, although it is important to note that all drugs are potentially harmful.

Drugs can also be addictive, and some are more addictive than others. For example, a staggering 1 in 4 first-time users of heroin will become addicted, whereas about 10% of cannabis users will develop an addiction to cannabis. Drug addiction greatly increases your risk of having serious long-term mental and physical health problems.

Use and supply of drugs are often linked to crimes, some of which may be violent. Nearly half of all deaths caused by knife crime in the UK are directly linked to drugs. Drug-related crime has huge impacts on the community, including financial, physical and emotional welfare.

Drug classifications are determined by parliament. The Advisory Council on the Misuse of Drugs (ACMD) makes recommendations to the government about which drugs should belong to which class, taking into consideration the level of harm to health and society.

It is rare that the government will change the class of a drug once it has been assigned. Cannabis is one of the few drugs that has changed drug classification in the UK. Historically, cannabis was a class B drug until it was downgraded to a class C drug in 2004. In 2009, cannabis was reclassified as a class B drug.

The drug classifications also impact how people who use, supply or produce drugs are sentenced in court. People who are charged with possession or possession with intent to supply class A drugs can receive harsher sentences than those sentenced for class B or C related offences.

What are the classes of drugs?

There are three types of drug classifications, and one temporary drug class. In this section, we discuss the types of drugs you can find in each class.

It’s important to note that the lists in this article are not exhaustive. To see a more extensive list of controlled drugs and which class they belong to, visit the UK Government website.

Class A

Class A drugs are considered the most harmful to health and society, and therefore carry the harshest penalties. Drugs belonging to this class are also usually the most addictive compared to class B or C drugs.

Class A drugs include:

  • Heroin
  • Methadone
  • Cocaine (including crack cocaine)
  • Ecstasy (MDMA)
  • LSD (lysergic acid diethylamide)
  • Magic mushrooms
  • Methamphetamine (crystal meth)

The effects of these drugs have strong effects on your mental state.

Heroin and methadone can make you feel relaxed, sleepy and happy. Heroin can give users feelings of euphoria or intense pleasure.

Cocaine, ecstasy and methamphetamine can make you feel energetic, alert and excitable.

LSD and magic mushrooms are psychedelics that can make you see, hear or feel things that aren’t there. People who use these drugs often have ‘trips’, which may be good or bad. The type of trip you have can depend heavily on your mood before taking the drug.

Despite some of the ‘desirable’ side-effects mentioned above, taking any of these drugs can have serious consequences.

LSD and magic mushrooms aren’t considered to be addictive, but their use can often become problematic for some people. Bad trips can lead to an individual hurting themselves or others around them. LSD and magic mushrooms can exacerbate mental health issues in some people.

‘Comedowns’ might be experienced by recreational users of cocaine, methamphetamine and ecstasy. Comedowns happen when the drug has cleared the bloodstream and is no longer having an ‘elevating’ effect on the brain. People experiencing a comedown will usually have a low mood and might even experience paranoia, panic attacks or anxiety.

In people who are dependent on drugs, a comedown is usually the first stage of drug withdrawal. Drug withdrawals can be very unpleasant, and those who are in withdrawal might seek out more of the drug to stop the symptoms from happening, thus propelling the cycle of addiction.

Using too much heroin, methadone, methamphetamine, cocaine or ecstasy can also cause you to overdose. Overdoses can be very dangerous and may even be fatal. The risk is magnified if you use other drugs, including alcohol, at the same time.

In the UK, heroin overdoses kill more people than any other illegal drug (Talk to Frank). Heroin is also extremely addictive, with about 1 in 4 first-time users becoming addicted.

There are lots of different short- and long-term health risks associated with using class A drugs. You can find out more by visiting the NHS website or Talk to Frank.

Class B

While class B drugs are still harmful to both your health and society, they are considered less harmful than class A drugs.

Class B drugs include:

  • Cannabis
  • Ketamine
  • Synthetic cannabinoids (e.g. black mamba, spice)
  • Amphetamines
  • Barbiturates
  • Synthetic cathinones (e.g. mephedrone)
  • Methylphenidate (Ritalin – ADHD medication)
  • Codeine
  • Gamma-hydroxybutyrate (GHB – ‘date-rape’ drug)
  • Gamma-butyrolactone (GBL – GHB precursor)

These class B drugs have varied effects on your body and mind, depending on which drug you take.

Some class B drugs, like class A, are addictive, and there is also a risk you can take too much and overdose on them.

Class B drugs like codeine, methylphenidate and barbiturates, are prescription drugs. That means it’s illegal to be in possession of them if you don’t have a valid prescription. These drugs are usually safe when taken as prescribed. However, if abused or taken illegally, they can lead to overdoses and addiction.

Ketamine is licensed to be used in hospitals as an anaesthetic, but its use recreationally is illegal. Like other class B drugs, you can overdose on ketamine and become addicted to it.

People sometimes take controlled prescription or licensed drugs like codeine or ketamine because they like the effects the drug has on their body. It’s important to remember that taking drugs that have not been prescribed to you by a medical professional is incredibly dangerous and can easily lead to accidental overdose, addiction, and even death.

GBL and GHB produce symptoms that are similar to alcohol consumption. GBL is turned into GHB in the body. It is very easy to overdose on GBL or GHB. GHB is sometimes called the date-rape drug because its use (e.g. ‘spiking’ drinks with GHB) has been linked to sexual assault and rape crimes. GBL and GHB are also addictive.

Cannabis is the most consistently used drug in England and Wales (Office for National Statistics, 2022). Synthetic cannabinoids are man-made to produce similar effects to tetrahydrocannabinol (THC) found in cannabis. They are more dangerous than using normal cannabis because the synthetic component reacts more potently in the body.

Class C

Class C drugs are assumed to be the least harmful to health and society.

They include drugs such as:

  • Anabolic steroids
  • Piperazines
  • Benzodiazepines (diazepam)
  • Nitrous Oxide (laughing gas)
  • Khat

Anabolic steroids are a class of drugs that are similar in structure to testosterone, the male sex hormone. They aren’t taken to achieve a ‘high’. Instead they are used by some people (e.g. some athletes or body builders) to build muscle mass, or help them to train longer.

Anabolic steroids also have a limited use in the medical field and are safe when administered correctly by a medical professional. Abusing anabolic steroids can lead to many physical and mental health problems, like infertility, kidney or liver problems, heart attacks, as well as paranoia or aggression. You can become dependent on anabolic steroids and experience withdrawal.

Piperazines are a large class of chemical compounds that are used in the manufacture of things like plastics and brake fluid. Some piperazines (e.g. piperazine adipate) are used to treat some types of parasitic infections. Piperazines are also found in some anti-depressants. When abused, the drug feels like a less potent version of ecstasy (MDMA). As piperazines are stimulants, fits and heart attacks are real risks, even for healthy individuals.

Benzodiazepines such as diazepam (Valium) or alprazolam (Xanax) are prescription medications used to treat anxiety. They slow the brain down in a similar way to alcohol, and can make you feel drowsy, confused and potentially cause you to become unconscious.

Street benzodiazepines (or ‘benzos’) are very dangerous. They are sometimes packaged to look like a legitimate prescription pack, but the potency can be much higher. It can be easy to overdose on benzos and taking too much can lead to death. Benzos have also been linked to drink spiking and sexual assault crimes.

Nitrous oxide, or laughing gas, has many industrial and medical uses. In medicine, it is used as an anaesthetic and analgesic (pain relief). It is also often used to make whipped cream. People who abuse nitrous oxide usually inhale the gas from a balloon, making them feel relaxed or giggly. The effects are felt almost instantly but wear off after a couple of minutes.

In November 2023, illegitimate possession or supply of nitrous oxide was made illegal and the gas was listed as a class C drug. Nitrous oxide can be very dangerous, and people have died after taking too much. There is also evidence that you can become psychologically dependent on nitrous oxide.

Khat is a leafy green plant that is chewed. Its effects are similar to amphetamine but less powerful. It’s not considered to be physically addictive, but users can become dependent. There is also a risk of liver toxicity if used excessively.

Temporary class drug orders

A temporary class drug order (TCDO) gives the government power to temporarily ban a new drug for up to one year while they decide how to classify the drug.

After the one-year ban, the drug is either assigned to a class, or an extension may be made if more time is needed to make a decision.

For the government to issue a TCDO, the drug in question must meet certain criteria:

  • The drug must not already be controlled as class A, B or C
  • The drug is being, or is likely to be misused
  • The drug is having, or is capable of having harmful effects

An example of a drug that has received a TCDO is methylphenidate. Methylphenidate is a common drug used to treat ADHD. It can also be used to treat narcolepsy in some cases.

Methylphenidate was being sold as an uncontrolled stimulant drug and so some methylphenidate derivatives were placed under a temporary class drug order in 2015.

This meant that anybody found in possession of methylphenidate would have it confiscated, and anybody found dealing the drug could be sentenced to a maximum of 14 years in prison and/or an unlimited fine.

Methylphenidate derivatives remained banned under the TCDO temporary class drug order for two years before being reclassified as a class B drug, where it remains to this day.

It is not an offence to simply be in possession of a drug under a TCDO, but it is illegal to supply or produce it.

What are the penalties for possessing drugs?

The penalty for possessing drugs depends on the amount and type of drug you have been caught with.

It is illegal to be in possession of any controlled drug without a legitimate reason. A legitimate reason for being found in possession of a controlled drug is if you have a prescription for it. Such drugs include codeine, methylphenidate, and methadone. If you are suspected of supplying a controlled drug, even if you have a prescription for it, you may be charged with possession with intent to supply.

If you are caught in possession of cannabis or khat, and it is not suspected that you are supplying it, the police can give you a warning, caution, or an on-the-spot fine, if it is your first offence. If you are repeatedly caught in possession of these drugs, you are likely to receive a much harsher penalty.

Being in possession of drugs doesn’t just mean on your person, e.g. in the pockets of your trousers. Having drugs in your car or in your house also constitutes possession.

You can be charged for illegal drug possession even if the drugs don’t belong to you. If somebody asks you to keep drugs for them, you should always say no, even if you don’t intend to use them. If you are caught, you can be charged with possession.

It is not an offence to possess anabolic steroids for personal use, but it is an offence to supply or produce anabolic steroids (GOV UK). Regardless, abusing any controlled substance is very dangerous.

It is also not an offence to be in possession of a temporary class drug. It is however an offence to supply, produce or deal a drug that is controlled under the temporary class drug order.

There are different penalties for different classes of drugs:

  • Possession of class A drugs – up to 7 years in prison and/or an unlimited fine
  • Possession of class B drugs – up to 5 years in prison and/or an unlimited fine
  • Possession of class C drugs – up to 2 years in prison and/or an unlimited fine
  • Possession of temporary class drugs – no penalty, but police may confiscate the drug

What are the penalties for supplying and dealing drugs?

Supplying and/or producing drugs is a much more serious offence than possession alone. The supply and production of drugs in the UK is an enormous financial burden to society when considering the cost of healthcare and criminal justice.

Drug dealing in the UK is thought to be a major cause in the increase of serious violence. Drug-related violence has a big impact on the emotional, physical and financial wellbeing of the victims. The impact of drug dealing on the health and wellbeing of society is reflected in the harsher penalties available for the supply of drugs, compared to possession alone.

If the police catch you with drugs, they will try and determine what class of drugs you are carrying, as well as the quantity.

Drug paraphernalia, equipment or other evidence may also be considered if you are caught in possession of controlled substances. This might include scales, deal bags, clingfilm, cutting agents, ‘burner’ phones (a phone that is usually cheap and allows someone to communicate anonymously or temporarily), lists of customers, or cash (usually in large quantities).

If you are caught holding drugs for a friend, you might be charged with intent to supply, even if the quantity is small. If someone asks you to keep hold of their drugs, you should always say no. You could be fined, sentenced to prison, or both.

Participating in the manufacturing or cultivation of controlled drugs is also illegal. This includes providing a premises or equipment for the production of illegal drugs.

There are different penalties for supplying, dealing or producing drugs, depending on the drug classification:

  • Class A drugs – up to life in prison and/or unlimited fine
  • Class B drugs – up to 14 years in prison and/or unlimited fine
  • Class C drugs – up to 14 years in prison and/or unlimited fine
  • Temporary class drugs – up to 14 years in prison and/or unlimited fine

Are there factors that can affect the level of penalties?

The magistrates or judge will determine what penalty you will receive for a drug offence based on the evidence provided and any aggravating or mitigating factors.

The judge or magistrates use the sentencing guidelines to determine which sentence they can give to an offender. Each offence has a ‘starting point’ – the point at which the provisional sentence is calculated. Aggravating or mitigating factors are then considered, which can increase or decrease the sentence.

An aggravating factor is something that makes a crime more serious. If you are charged with possession, or possession with intent to supply, aggravating factors can mean you are sentenced more harshly.

Aggravating factors for drug-related offences can include:

  • Previous convictions, particularly if also drug-related
  • Committing the offence on bail or on licence
  • Attempts to conceal drugs or other evidence
  • Presence of a weapon
  • Threats or use of violence
  • High purity of the drug(s)
  • Presence of children or non-users
  • Possession of drugs in a school or prison

This list is not exhaustive. There are many aggravating factors that surround the possession, supply and production of drugs.

Mitigating factors are circumstances or facts that may lessen the severity of the crime, or the person’s culpability.

If you have committed a drug-related crime and there are mitigating factors surrounding the crime, with very few or no aggravating factors, then you will likely receive a lighter sentence.

Mitigating factors could include:

  • No previous convictions or no relevant previous convictions
  • Good character who demonstrates exemplary conduct
  • Remorse
  • Low purity of the drug
  • Offender pressured to be involved in possession/supply
  • The offence was an isolated incident
  • Offender has demonstrated steps to address any addiction issues or offending behaviour (e.g. rehabilitation)
  • Learning disabilities or difficulties

You can find out more about the penalties for possession, supply or production of drugs on the government website, or the sentencing guidelines website.

Where can I get a drug test?

At AlphaBiolabs, we offer a range of drug tests for different purposes.

As an accredited drug testing laboratory, we are well placed to support you with your drug testing needs, whether you have concerns about a loved one misusing drugs, and want a test for peace of mind, or you are a member of the public who requires a legal drug test for official matters.

We also offer drug testing for legal professionals and social workers, and employers looking to discourage drug abuse in the workplace. Our UK laboratory is fully equipped to test a variety of samples for the presence of drugs including hair, nails, urine and oral fluid.

For more information about the drug testing on offer at AlphaBiolabs, call our Customer Services team on 0333 600 1300 or email info@alphabiolabs.com.

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Liz Wood, AlphaBiolabs

Liz Wood

Health Testing Specialist at at AlphaBiolabs

Liz joined AlphaBiolabs in 2021, where she holds the role of Health Testing Specialist.

As well as overseeing a range of health tests, she is also the lead on several validation projects for the company’s latest health test offerings.

During her time at AlphaBiolabs, Liz has played an active role in the validation of the company’s Genetic Lactose Intolerance Test and Genetic Coeliac Disease Test.

An advocate for preventative healthcare, Liz’s main scientific interests centre around human disease and reproductive health. Her qualifications include a BSc in Biology and an MSc in Biology of Health and Disease.

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