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In this booklet, when we say ‘cannabis’, we mean ‘herbal cannabis’ or what’s commonly called skunk, weed, herb, grass, green, or bud. But names can change depending on where you live.

It’s the dried flowers and leaves of the cannabis plant, different from hashish (resin) or synthetic cannabinoids like spice.

Increasingly, cannabis is consumed in herbal rather than resin form. It’s usually smoked in joints, pipes, or vaporisers, but can also be drunk as a tea, or eaten in some kind of bake or cooking.

Over the last 30 years, cannabis has been the most used illegal drug in England and Wales. The most recent UK figures (taking us to March 2023) suggest just over 2.6 million adults aged 16 to 59 used cannabis in the last year. The true figure is probably much higher.

These days, a significant amount of herbal cannabis is grown in the UK, but we still import a substantial amount, particularly cannabis resin, from Europe and North Africa.

The information on this page will help you understand what cannabis is, the warning signs of developing a problem, reducing the risks, and how to cut down or stop.

The cannabis plant contains hundreds of naturally occurring chemicals – sixty of which, known as cannabinoids, are unique to the plant.

Out of these, two chemicals matter when it comes to getting stoned: THC (tetrahydrocannabinol), which is the main psychoactive substance, and CBD (cannabidiol).

THC is responsible for the euphoric high and that feeling of being ‘stoned’. It can also make you feel paranoid and anxious, particularly if the cannabis you’re taking contains high levels of THC.

CBD, on the other hand, has a calming and relaxing effect.

It’s possible the CBD might cancel out some of the paranoia or anxiety that comes from the THC – but the evidence is mixed on this.

If herbal cannabis gives you panic attacks or makes you feel edgy and anxious, it’s best to stop using it. If you can’t, or don’t want to stop, try switching to resin (hash), which has higher levels of CBD.

Strength describes the intensity of the high from cannabis, while potency refers to the percentage of THC in the
plant’s resin.

Less resin with high THC will produce a higher high than more resin with low THC. The strength also varies based on the plant variety, cultivation method, part consumed, preparation, and storage.

In the early 2010s, average THC content in cannabis was lower than today. By the early 2020s, THC levels had risen significantly, with strains like ‘skunk’ bred for high THC. Advances in cultivation techniques continue to produce even more potent cannabis strains.

Not everyone who uses cannabis will  develop mental health problems. 

However, evidence suggests that it may worsen existing mental health issues in some people, particularly if they’re smoking cannabis that’s high in THC. It may also bring on mental health issues, such as psychosis, in anyone with an condition they may not have been aware of. 

Cannabis users with close relatives who have episodes of psychosis or schizophrenia might have a higher genetic risk of experiencing similar issues.

Psychosis includes hallucinations and delusions. 

Hallucinations make someone experience things that other people aren’t, including hallucinations or
hearing voices. 

Delusions are when people have unusual beliefs that other people don’t, and feeling detached from reality.

Schizophrenia is a mental illness that affects how someone thinks or feels. Symptoms of schizophrenia include hallucinations and delusions. But often it will have other symptoms like feeling flat or emotionless or withdrawing from other people.

If you feel your cannabis use is affecting your mental health, you should stop using it. If you can’t stop, try using a less potent form of cannabis, like cannabis resin (hash) and get medical help or talk to your local drug and alcohol service.

Young People and Mental Health

Teenagers and young adults, whose brains are not yet fully developed, are particularly at risk of mental health issues. Studies have found that starting and regularly using cannabis at a young age can lead to lasting cognitive problems, which don’t fully go away, even if the person quits using cannabis later in life. 

Physical Health

Smoking harms the lungs. Inhaling any burning organic matter releases harmful toxins into your body. Cannabis can also contain pesticides and
fertilisers used during its production, as well as bacteria which grows on the buds and can compromise the immune system. This can be a problem for those living with HIV/AIDS or, cancer.

Some people have a positive experience using cannabis, but it can become an issue for others. 

You may be getting bored with being stoned. It might be affecting your health, draining your finances, and interfering with your relationships, education, or work. 

If you’ve been using more cannabis than before, feel moody or irritable without it, spend a lot of time acquiring and recovering from its effects, and notice that it’s replaced other activities you used to enjoy, it might be time to consider cutting down or stopping.

If you recognise any of these, it could be time to think about your cannabis use. 

There are several steps you can take, which may help.

1. Think about why you want to change

 Put together a list of pros and cons about your cannabis use

You can refer to this during moments of weakness, to remind yourself why you decided to make changes in the first place.

Create a cannabis diary

Create a diary of how much you smoked in the last week or two. Make a note of how much you spent, where you smoked and who you were with. It will help to motivate you and identify high-risk situations

 2. Plan ahead

Tell your friends or family that you intend to break the habit

It makes it easier to refuse a joint when it’s offered, and your friends and family understand more if you’re being a bit on edge.

Think about high-risk situations

Take temptation away by avoiding situations where you’d normally getting stoned. 

 Cravings and withdrawal symptoms

Withdrawal symptoms will depend on how much you normally smoke and how long you’ve been smoking. They can include any of the following: 

• irritability
• a craving to smoke 
• anxiety
• depression
• anger
• confusion

 They can have a physical effect on you such as the following:

• problems sleeping 
• restlessness
• loss of appetite
• tremors
• sweating (mainly at night)

Symptoms start between one and three days after stopping cannabis and last for around two weeks. They’re not harmful and are in fact a positive sign that your body is adapting to being.

Cravings last only a few minutes so if you can distract yourself for about 10 minutes whenever you get one (such as going out for a walk), then the urge will pass and each one will get easier. 

Start to cut down

Some people find it easier to give up completely by cutting down on their cannabis use beforehand. Delay the first smoke of the day, put less cannabis in each joint, or simply have fewer joints.

 3. Getting on with it

Deal with high-risk situations

Clear your flat of any cannabis paraphernalia, including skins, pipes, bongs, etc. Delete your dealer’s number from your phone.

Stay active

Doing an activity will help take up the space in your head that cannabis occupied.

Do something new

Start a new hobby or enrol on a course.

Look after yourself

To lower your stress levels, eat a healthy diet, get as much sleep as you can, drink plenty of water and exercise. 

4. Keep going

You might not succeed the first time, especially if you’ve been smoking cannabis a long time. Don’t beat yourself up about it. You haven’t failed, you’ve just taken the first step. Try again. It’ll probably be easier next time.

Cannabis is illegal. It is a class B drug. It’s against the law to possess, sell, give away, grow, or let your premises be used for smoking it

Possession can get you up to 5 years in prison, an unlimited fine, or both. Supply and production can result in up to 14 years in prison, an unlimited fine or both. 

Some police forces will deal with possession for personal use by steering you away from the criminal justice system, especially if you’re under 18. Instead, they pick from the following options:

• Issue a warning.
• Make you pay an on-the-spot fine. 
• Give you a ‘community resolution’ (e.g. make you do an educational course on drugs). You won’t get a criminal record, but it will show up on an enhanced DBS check.  
• Issue a ‘conditional caution’ (e.g. a rehabilitation course, unpaid work, or a fine). A conditional caution will go on your criminal record. 

A persistent offender will be prosecuted. Find out about penalties here: 

gov.uk/penalties-drug-possession-dealing 

If you’re under 18

The police will make a note of the incident. A first offence might receive a youth caution, which is a formal warning. If it’s not your first, you might get a youth conditional caution, which could involve attending drug education and support programmes. This approach is intended to keep you out of the criminal justice system and to support, rehabilitate and educate instead.

For repeat offences, you could be taken to youth court, which might result in fines, community orders, or even detention. Initial cautions aren’t criminal convictions, but are recorded and can affect future opportunities and travel.

Growing cannabis 

People growing a small number of plants can often be charged with possession, supply and production. If convicted, you could get a short prison sentence. Commercial growers face even longer inside.

Drug driving

You might think that cannabis is safer than alcohol, but it slows down reactions and focus wanders. It can also cause paranoia, drowsiness, distorted perception and a sense of disorientation – all of which could make you lose control.

The effects of cannabis fade after a matter of hours, but it can be detected in your body for up to four weeks. 

It’s illegal to drive with over the permitted level of cannabis in your system. If you test positive, you can receive a driving ban, large fine, or go to prison.

A criminal record can affect your future employment and travel.

Even spent convictions that don’t need to be declared can show up.

There are also lots of everyday jobs that require an ‘enhanced check’ such as teaching, driving a taxi and becoming a soldier. 

Each country has its own set of laws on drug convictions, which might cause you travel problems.

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Cumbria, Northumberland, Tyne and Wear NHS Foundation Trust

DRD Co-ordinator (Aberdeenshire)

Life+

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Growing up can be tough; always under pressure from your friends and family to do the right thing - look right, sound right and behave right.

But, as a young person, what is the right thing when it comes to drugs and alcohol? should you take that white powder or neck that pill? What’s in it, how will it make you feel, what are the risks?

The only way to avoid the risks of using drugs and alcohol is not to use them at all. If you use drugs and alcohol or are thinking about it, it’s essential to learn as much as you can about the substances you are using.

This page provides you with clear, non-judgemental information about some of the most commonly used legal and illegal substances, including:

• Alcohol
• Amphetamine
• Cannabis
• Cocaine
• Ecstasy
• Ketamine
• Nitrous oxide
• Mephedrone
• Solvents

The final section in this booklet is called ‘Staying Safe’. It includes information about mixing drugs and alcohol, feeling unwell, and looking after yourself and your mates.

The amount of alcohol in a drink is measured in units. Different drinks have a different number of units. The number of units in a bottle or can of alcohol is printed on the label or packaging.

The effects of alcohol

• Can slow down your brain which, in small amounts, can make you feel relaxed and sociable.
• Can cause slurred speech, blurred vision, confusion, loss of coordination, and heightened emotions, the more you drink.

The problems with alcohol

• Can damage your liver, stomach, kidneys, brain, muscles, skin and bones and causes cancer.
• Can cause impotence (brewer's droop), infertility (shooting blanks), shrink the testicles, and grow breasts, in men.
• May cause loss of periods, infertility (can't have a baby), and fat redistribution, in women.
• Can cause addiction.
• Can result in unconsciousness and sometimes death, if you drink a lot very quickly.

Young people, under 16, should not drink alcohol at all as this can damage developing organs. The best advice is not to drink alcohol until you're 18.

When over 18, men & women should drink no more than 14 units a week, spread evenly across a few days with a couple of alcohol-free days.

Alcohol and the law

If you are under 18 it is against the law for you:

• To sell you alcohol or for an adult to try and buy it on your behalf.
• To buy alcohol, attempt to buy alcohol, or to be sold alcohol.
• To drink alcohol in licensed premises, with one exception - 16 and 17 year-olds accompanied by an adult can drink (but not buy) beer, wine, and cider with a table meal in a pub or restaurant.

The effects of amphetamines

• Can speed up your heartbeat and breathing.
• Can also cause anxiety, paranoia, irritability, twitchiness and insomnia.

The problems with amphetamines

• Can lead to tolerance, meaning you have to take more to get the same effect.
• Excessive use can lead to psychosis (loss of contact with reality), chest pain, heart problems and high blood pressure.
• Can cause something called formication, which is the excessive itching and scratching of the skin, leading to skin infections.
• The purity of some amphetamines can be as low as 5%.

Amphetamines and the law

• Amphetamines are illegal, Class B drugs. 
• Possession of Class B drugs carries a maximum sentence of 5 years' imprisonment and a fine. 
• Supplying (selling or giving away) carries a maximum sentence of 14 years' imprisonment and a fine.

Cannabis comes from a plant called Cannabis Sativa.
Cannabis normally comes in a solid brown lump called hash (the resin scraped from the plant), or the dried flowers of the plant, known as grass, weed or Skunk.

The main chemical in cannabis is called THC (Tetra-Hydro-Cannabinol), which is the bit that makes you feel trippy. Different types of cannabis have different levels of THC.
It is normally smoked, rolled with tobacco in cigarette papers, or in a pipe or bong, but it can also be eaten.

The effects of cannabis

• Cannabis can make you feel relaxed, trippy, talkative and giggly.
• It can make you feel tired, lazy and sleepy.
• Can make colours, music and taste seem more intense.

The problems with Cannabis

• Cannabis can cause paranoia, anxiety and panic attacks.
• In some people, cannabis can bring on mental health problems.
• The earlier you start smoking cannabis, the more likely you are to have problems with it.
• Can cause lung damage if smoked.
• Cannabis become a habit and lead to a lack of motivation and problems concentrating at school or work.

Cannabis and the law

• Cannabis is an illegal, Class B drug.
• It is illegal to have, sell, grow or give away.
• If you are under-18 and caught with cannabis your parents or guardian will be contacted, you could get a reprimand and possibly a referral to a Youth Offending Team.
• If you are over-18, a first-time offence will usually get you a 'cannabis warning,' a second offence will get you an on-the-spot fine, and a third offence will result in prosecution and a criminal record.

There are products which claim to have the same effects as cannabis (Spice, Black Mamba, etc.), but these can also be harmful and are illegal under the Psychoactive Substances Act 2016.

Cocaine is a substance obtained from the leaves of the coca plant.

It normally comes in a white powder form. The purity of cocaine can vary greatly throughout the UK, from between 15-55%.

The effects of cocaine

• Can cause an energy rush, and feelings of exhilaration, confidence and wellbeing.
• Can also cause effects like edginess, paranoia, anxiety and shaking.

The problems with cocaine

• Cocaine is normally snorted through a rolled-up note or straw. The cocaine and the chemicals it is mixed with are acid and can burn or damage your nose.
• The note or straw you use may have been up others peoples' noses and can be covered in snot, viruses and germs.
• The initial effects of cocaine only last between 15 and 30 minutes. Using again and again to achieve the same effect can lead to tolerance, where you have to use more and more to get the same buzz further down the line, addiction.
• Cocaine increase blood pressure, heart rate and body temperature.
• Using cocaine increases the risk of stroke or a heart attack.
  
  

Cocaine and the law

• Cocaine is an illegal, Class A drug.
• Possession of Class A drugs carries a maximum sentence of 7 years imprisonment and/a fine.
• Supplying (selling or giving away) carries a maximum sentence of life imprisonment and a fine.

MDMA usually comes in tablet form, known as 'ecstasy', or powder, known as 'MDMA powder.'

Tablets come in various shapes and colours. MDMA powder usually comes in white or off-white crystals or powder.

Remember, not all tablets claiming to be ecstasy or powder claiming to be MDMA, actually contain any real MDMA.

The effects of ecstasy

• Can cause an initial rush, jaw clenching, nausea, and nervousness.
• Can increase energy levels and give a warm 'loved-up' huggy feeling.
• Can cause sounds, colours, and feelings to be more intense.

The problems with ecstasy

• Ecstasy can cause you to overheat, particularly if you are jumping up and down (sometimes called dancing!) in a nightclub and don't drink enough liquid, take a break, or get some fresh air.
• Ecstasy causes your body to retain water (you can't pee!) which alters your body's chemical balance.
• If you also drink a lot of water, this can cause your brain to swell.
• Deaths from ecstasy have often been caused by drinking either not enough or too much water.
• Your body needs about a pint of fluid - water, isotonic drink or fruit juice - an hour, to function properly in a hot environment.
• Ecstasy normally takes half an hour to an hour to start working but can take longer. Being impatient and taking more can increase the dangers.
  The comedown from ecstasy can leave you feeling tired and depressed for a few days afterwards.

Ecstasy and the law

• Ecstasy is an illegal, class A drug.
• Possession of Class A drugs carries a maximum sentence of 7 years imprisonment and/or a fine.
• Supplying (selling or giving away) carries a maximum sentence of life imprisonment and a fine.

Ketamine is an anaesthetic that comes in the form of a clear liquid, tablets, or powder ranging in colour from off-white to light brown.

The effects of Ketamine

• The effects of Ketamine vary depending on your environment. In small doses it normally acts as a stimulant, boosting your energy levels, and making you feel high and trippy.
• Larger doses can cause a strange 'out-of-body' effect, with hallucinations, feelings of calm and serenity, distorted reality, panic attacks, unpleasant feelings and fear.
• These feelings can last up to 90 minutes.
• The out-of-body experience is known as being in a 'K hole'.
  Physical effects can include loss of control over your body, loss of coordination, difficulty speaking, moving, hearing and seeing (delirium), numbness and nausea. 

The problems with Ketamine

Obviously, if you are having an out-of-body experience and can't move your arms and legs, then you're particularly at risk, especially in unfamiliar surroundings.

Because Ketamine is an anaesthetic and numbs your body, you can't feel pain as much as you would normally, so you can injure yourself without realising.

• Regularly using a lot of Ketamine can cause serious bladder problems, with severe pain and difficulty peeing.
• Too much Ketamine can affect your breathing, leading to unconsciousness or heart failure.
• Ketamine can be addictive.

Ketamine and the law

• Ketamine is an illegal, Class C drug.
• Possession of Class C drugs carries a maximum sentence of 2 years imprisonment and/or fine.
• Supplying (selling or giving away) carries a maximum sentence of 14 years imprisonment and a fine.

Mephedrone (4-Methylmethcathinone) also known as Meph, Meow Meow, M-Cat, is a synthetic chemical, similar to amphetamines.

Usually an off-white powder. Normally found in tablets or capsules. It can have a sharp chemical or fishy/bleachy smell.

Effects of Mephedrone

• Feelings of wellbeing,
• alertness,
• increased confidence and becoming more talkative.

Adverse effects of Mephedrone

• Increased heart rate.
• Palpitations, heavy sweating.
• Blurred vision.
• Hot flushes.
• Irregular heartbeat.
• Nausea, and muscle tension, especially in the face and jaw.

The main after-effects are tiredness, feeling dizzy and feeling low.

The problem with Mephedrone

• Can be mixed with unknown substances.
• Damage to the nose through snorting.
• Anxiety, panic attacks and agitation.
• Raised blood pressure, which can lead to heart problems and strokes.

Stimulants can cause you to overheat, especially if you are bouncing around in a nightclub.

There isn't enough information around at the moment to predict if Mephedrone is addictive or will cause long-term damage to your health.

Mephedrone and the law

• Mephedrone and other cathinone-based substances are illegal to possess, supply or produce.
• It is a class B drug.
• Possession could get you up to 5 years in jail and a fine.
• Supplying (even giving it away) gets up to 14 years in jail and a fine.

Nitrous oxide is a colourless and mainly odourless gas. It's Common street names include laughing gas, noz or noxy.

It comes in small, silver pressurised containers (bulbs) or large canisters, usually transferred from a canister into a balloon for inhaling.

> The effects of nitrous oxide

Users feel light-headed, dizzy, giggly, and euphoric.

You may experience sound distortions and hallucinations – when you see or hear things that aren’t there. It can also cause confusion, headaches, nausea, and paranoia.

 > The problems with nitrous oxide

Using pressurised gas directly from a canister is dangerous.

Inhaling in an enclosed space or putting your head in a bag of gas can lead to unconsciousness.

Using it in hazardous locations, like high buildings or close to water etc., is risky.

Prolonged and heavy use can result in vitamin B deficiency and nerve damage.

Symptoms of nerve damage can include numbness or pins and needles in the arms and/or legs.

Excessive use can cause breathing difficulties and heart problems.

The law: nitrous oxide is a Class C drug. Supply or possession with the intention of using it to get high is illegal.

Solvents come in many forms, such as household products like glues, lighter fluid and aerosol sprays, and are normally inhaled.

The effects of solvents

• Can cause intoxication (feeling very drunk), dizziness and drowsiness.
• Can cause sickness and vomiting.
• Can lead to aggressive and risky behaviour.

The problems with solvents

• Can cause your heart to beat irregularly or stop, even on first-time use. This can happen whether they are sniffed from a bag, an aerosol or sprayed into your mouth.
• Can cause loss of consciousness. If you use solvents in a dangerous location or place your head inside a bag, there is the added danger of having an accident or suffocating.
• Can cause burning or a rash around your mouth and nose.

Solvents and the law

• It is illegal to supply solvents to persons under the age of 18 if the supplier knows or suspects the product will be sniffed.

Low and slow

Give drugs time to work - rushing to take more is risky. Effects vary based on how you feel, where you are, and what’s in them, so take it slow.

Synthetic opioids

Be aware that drugs are increasingly being mixed with dangerous synthetic opioids like nitazene and fentanyl, which can cause overdose even in tiny amounts. You won’t be able to see, smell, or taste them - take it slow and be careful.

Avoid using drugs alone

Never use drugs alone - it’s dangerous, as no one can help if things go wrong. Have a friend present who knows what you’ve taken. If someone becomes unresponsive, put them in a recovery position (on their side, top knee and arms bent), check their breathing, call 999 and be honest about what they’ve taken so medics can help properly.

Mixing drugs and alcohol

Using drugs and alcohol together can be unpredictable and dangerous, especially since alcohol dehydrates you. Mixing cocaine, ecstasy, or other substances with alcohol can put you at serious risk.

Pre-loading

Having drinks while getting ready might seem like a good way to start the night, but it makes you more likely to get into trouble later. Take it easy - the night’s just beginning!

Pace yourself

Want to make your night last? Have food first, grab water between drinks, and don’t feel pressured to drink every round. Put your drink down between sips - holding it means you’ll drink faster.

Violence

Keep your cool if someone’s giving you grief - walking away might feel tough, but it’s better than getting hurt or in trouble.

Sex

If you’re planning to hook up, bring protection and use it. Emergency options are available if needed - visit your GP, walk-in centre, or pharmacy within 72 hours.

Don't flash your valuable

Keep your phone and valuables safe - consider bringing a backup phone for nights out. Be careful at ATMs - shield your PIN and stay aware of your surroundings.

Keep an eye on your drink

Never leave your drink unattended or take one from someone you don’t trust.

Looking after yourseleves and your mates

We all need to look out for each other! If you’re heading off with someone new, let your friends know where you’re going. Maybe even send them a quick photo of who you’re leaving with.

If a friend’s feeling unwell, get them somewhere quiet and cool, keep them sitting up, and give them water. If they’re not responding, put them in the recovery position and get help immediately.

Getting home safely

Plan your journey home before you go out - it makes everything easier! Pre-book a taxi if you can, and arrange a meeting point in case you get separated from your friends. If you end up walking, stick to well-lit streets and main roads, no matter how tempting those shortcuts might be.

Remember - the best nights are the ones where everyone gets home safe!

What happens if you're caught with drugs, what will the police do, what are the legal options?

Supplying Drugs

Supplying illegal drugs includes possession with intent to supply, or give away for free to friends, and will almost certainly result in a criminal record, severe sanctions and possibly prison time.

Maximum penalties range from 14 years for Class C drugs to life imprisonment for Class A drugs.

Possessing Drugs

It’s illegal to be in possession of drugs and can get you from 2 to 7 years in custody, depending on the class of drug.

Out of court resolutions

If you’re found with a small amount for personal use, some police forces will take a different approach. They might opt to deal with the matter using what’s known as Out of Court Resolutions (OoCRs), with the following aims:

• Keep you out of the court system
• Help you address issues around drug use
• Divert you from repeat offending

Types of OoCRs

Community resolution: the police can make you attend an educational course on drugs and their anti-social effects to try to address the cause of your drug use.

Conditional caution: the police could opt for this if you’re a repeat offender when it’s not in the public interest to prosecute. It can include some kind of intervention to address drug use, such as referring you to a drug and alcohol service or other agency. It goes on your criminal record.

Restorative interventions: the police can consider these alongside a community resolution or conditional caution. You might need to attend drug awareness sessions or do community work and educational programmes.

OoCRs for children and young people

• Youth community resolution
• Youth caution
• Youth conditional caution

Additional things to consider

Failure to complete or engage with OoCRs will land you in court for the original offence.

If you’re under 18, the police are likely to inform your parents or carers.

A drug possession conviction can impact your life, such as restricting travel abroad (e.g. the US), or affect job opportunities.

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• What is mephedrone
• A short history of mephedrone
• What mephedrone looks like
• How mephedrone works
• The effects of mephedrone
• How to reduce the harm
• Mephedrone and the law
• Risks of different ways of using
• Long-term harm
• Overdose
• Mephedrone and chemsex

What is mephedrone

Mephedrone is a synthetic stimulant drug. It’s also known by its chemical name, 4-methylmethcathinone (4‑MMC). It is part of a group of drugs called cathinones, which are related to the natural stimulant cathinone found in the Khat plant.

People in East Africa (mainly Somalia and Ethiopia) have chewed Khat leaves for centuries. The effect is similar to caffeine and is used as a mild social stimulant.

In the UK, authorities classify the Khat plant as an illegal Class C drug.

A short history of mephedrone

Mephedrone (4‑methylmethcathinone or 4‑MMC) was first made in 1929, but it stayed under the radar for decades. In the early 2000s, underground chemists rediscovered the drug and began producing it for recreational use. They used old scientific research to recreate the cathinone-based drug and sold it online and in headshops as a “legal high” or “research chemical”. Because mephedrone wasn’t listed in the UK Misuse of Drugs Act 1971, it could be sold legally for a time, often labelled “not for human consumption” to avoid regulation.

Mephedrone became part of a wave of synthetic drugs known as legal highs, most of which were produced in China or India and sold online or in UK headshops.

To stay ahead of changing laws, underground chemists kept tweaking cathinone-like molecules. This led to the development of related drugs like methylone and MDPV (sometimes called monkey dust), which sellers often offered alongside mephedrone.

Mephedrone gained popularity in 2008 when MDMA purity dropped and ecstasy pills became less reliable. Many pills contained little or no MDMA and were instead filled with other substances, including mephedrone. People described the effects as euphoric and energetic—similar to MDMA, but shorter-lasting and more compulsive.

As use increased, so did hospital admissions and media panic. In April 2010, the UK government made mephedrone a Class B drug under the Misuse of Drugs Act. After the ban, wholesale prices jumped to around £4,000 per kilo, dealers doubled street prices, and producers were more likely to cut the drug with caffeine, glucose, MSG or mix it with other substances.

What mephedrone looks like

• Usually a white powder, visually similar to other ‘legal highs’
• Contents can vary even from the same source
• Sellers have mixed it with ketamine (‘Kit Kat’) or mis-sold crystal meth as mephedrone

How mephedrone works

Mephedrone triggers the release of noradrenaline (rush), dopamine (euphoria), and serotonin (loved-up feelings). The effects wear off quickly, often leading people to take more, increasing the risk of overuse and harm.

The effects of mephedrone

Common effects

• alertness
• elevated mood
• feeling energetic or excited
• calmness
• sociability and talkativeness

Common unpleasant effects

• dry mouth
• teeth grinding
• reduced appetite
• poor focus and short-term memory
• fast heart rate
• raised body temperature
• palpitations
• sweating
• anxiety or depression
• dilated pupils

How to reduce the harm

The safest option is not to use it. But if you do:

If you're going to use

• stick to small amounts (no more than half a gram per session)
• limit use to once a week or less

Slow and low

• take a small amount and wait
• don’t re-dose after 30–45 minutes

Stay hydrated and keep cool

• sip water, juice or isotonic drinks to stay hydrated

Avoid mixing with other drugs

• alcohol increases risk of confusion, aggression, overheating
• other stimulants increase risk of dehydration and heatstroke

Plan for the comedown

• rest, eat well, avoid alcohol
• take the next day off if needed

Mephedrone and the law

• mephedrone is a Class B drug under the Misuse of Drugs Act 1971
• possession: up to 5 years in prison
• supply or production: up to 14 years in prison

Risks of different ways of using

Long-term harm

• strong cravings suggest possible psychological addiction
• unknown long-term risks to brain, heart or liver
• animal studies suggest possible neurotoxicity

Overdose

Mephedrone increases heart rate, blood pressure and body temperature. Taking too much can cause seizures, hallucinations or overheating.

Early signs of overdose

• sudden rise in body temperature
• red or flushed face
• hot, dry skin with no sweating
• hallucinations or confusion
• muscle cramps or stiffness
• rapid breathing or panic

What to do

• stay calm and reassure them
• encourage slow, deep breaths
• cool them down with water, loosen tight clothing
• use wet towels or ice on the neck
• if they stop sweating or collapse, call an ambulance

If unconscious

• put them in the recovery position
• stay with them and tell medics what they took

Share this information

Raising awareness and sharing accurate information are effective ways to reduce harm. Services can order our mephedrone information booklet to share with people who use mephedrone, or share this guide with anyone who needs to understand the risks and effects more clearly.

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Cumbria, Northumberland, Tyne and Wear NHS Foundation Trust

DRD Co-ordinator (Aberdeenshire)

Life+

This ketamine harm reduction guide helps drug workers and services build the knowledge and confidence to engage with and support people who use ketamine

More people are using ketamine

Ketamine use has increased in recent years and is now common across a wide range of social settings. It was once mainly linked to the gay club scene but is now widely used at festivals, in student nightlife, and among people who use multiple drugs. In England and Wales, 3.8% of 16–24-year-olds — approximately 220,000 young adults — reported using ketamine in the past year (2022/23), the highest level recorded to date. Among adults aged 16–59, 0.8% — roughly 300,000 people — reported past-year use (ONS, 2024).

While many people use ketamine recreationally and without significant problems, drug services and outreach workers are reporting growing concerns. Some users are developing more frequent, chaotic, or dependent patterns of use, which can lead to a range of adverse side effects. As ketamine use continues to rise, drug workers and services are encountering more people who may benefit from harm reduction advice and support.

What is ketamine

Ketamine is an anaesthetic drug with dissociative effects. It was first developed in the 1960s and became widely used in surgery during the 1970s and 1980s. These days, it is used less often for routine operations but is still used in trauma cases such as burns or traffic accidents because it helps manage pain while maintaining breathing and blood pressure.

Is ketamine really a horse tranquilliser?

Ketamine is still used in human medicine in certain situations, such as emergency care and paediatrics but it is more commonly used as an anaesthetic in veterinary surgery — probably the source of the popular ‘horse tranquilliser’ misnomer. As a marketing ploy, something that could knock out a horse sounds like a winner for dealers and for media looking for an eye-catching headline. Even though it is mainly used on a wide range of small animals, ‘hamster tranquilliser’ just doesn’t have the same ring to it.

Non-medical use of ketamine

The non-medical use of ketamine became popular in the UK in the early 1990s rave scene, often sold in tablet form as ecstasy. These days ketamine is usually sold as ketamine and comes as a white powder that can be snorted (most common), swallowed (less common as it takes too long to work and acts as a laxative!), smoked (rare, as it tastes awful and wears off too quickly) or injected (very rare and not recommended).

When snorted, the effects begin within a few minutes and last around 30-45 minutes, depending on how much is taken. A common method in a club would be to dip the end of a key into the bag of powder and sniff a small amount (around 200mg) from the tip, known as ‘keying’. This short duration of action leads to re-dosing at regular intervals throughout the night. If swallowed, the effects begin around 15-30 minutes and last for 1-3 hours.

What are the effects of ketamine?

Despite what many users feel, ketamine is not a depressant drug and does not slow the heart. At anaesthetic doses, it usually increases heart rate and blood pressure. However, at low doses the subjective effects are often experienced as a slowing down and heaviness of the body — sometimes known as ‘sledging’.

Sought-after mental effects include a trance-like state, disconnection from reality, feelings of floating or flying, and visual (sometimes shared) hallucinations. The ketamine experience is very dependent on the setting in which it is taken. At low doses in clubs or raves, with loud music, lights, and the buzz of the crowd, it can feel stimulating, with increased energy and euphoria.

In quieter, more relaxed settings, such as at home with friends, users report transcendental or spiritual experiences — including apparent travel to other worlds, out-of-body sensations, re-emergence of long-forgotten memories, a sense of insight into existence, time distortion, or the feeling of dying and being reborn. However, panic, unpleasant feelings, and nightmare-like experiences can also occur.

Physical effects can include loss of body control, poor coordination, difficulty speaking, moving, hearing and seeing (delirium), numbness, and nausea. Among users, ketamine has sometimes been described as ‘psychedelic heroin’ or ‘L.A. coke’, highlighting the mixed and complex nature of its effects.

Short-term mental effects of ketamine

• Short-term mental effects
• Out-of-body experiences
• Shifts in perception of reality
• Confusion or disorientation
• Pleasant mental and/or body high
• Increased energy
• Euphoria
• Sense of calm and serenity
• Meaningful or spiritual experiences
• Enhanced sense of connection with the world (people, beings, objects)
• Distortion or loss of sensory perceptions (common)
• Open- and closed-eye visual hallucinations (common)
• Dissociation of mind from body
• Significant changes in the perception of time

Short-term physical effects

• Increased heart rate
• High blood pressure (hypertension)
• Respiratory depression (rare with ketamine alone but more likely when mixed with other depressants)
• Hypersalivation (excess saliva)
• Nausea
• Slurred speech
• Numbness and reduced sensitivity to pain (analgesia)
• Loss of coordination (ataxia)

What are the problems of using ketamine?

The main immediate risk with ketamine use is physical helplessness. Disconnection from the body, combined with loss of coordination and awareness, can be dangerous — especially in the disorienting environment of a club or rave. This is similar to being extremely drunk in a public place, where accidents are more likely. It can also leave users vulnerable to assault (physical or sexual) and to unprotected sex, increasing the risk of unplanned pregnancy, sexually transmitted infections (STIs) such as gonorrhoea, and blood-borne viruses (BBVs), including hepatitis B, hepatitis C, and HIV.

Fatal overdose from ketamine alone is very rare, as it typically does not cause life-threatening respiratory depression. However, loss of consciousness is dangerous in itself. If someone becomes unconscious after using ketamine, this is an emergency and should be treated as such.

Mixing ketamine with other drugs

Nowadays, many people use multiple drugs together, and ketamine is no exception. On a night out, people who use ketamine often combine it with substances such as alcohol (which increases risks), cocaine, and a range of newer compounds known as novel psychoactive substances (NPS).

There is also the added risk that ketamine may be contaminated with other substances — including potent opioids such as nitazenes — without the user’s knowledge. Contamination is an increasing concern in some drug markets, including ketamine.

Mixing drugs greatly increases risks, as the effects are unpredictable and harder to manage.

Is ketamine addictive?

Although not considered physically addictive, tolerance to ketamine builds up very quickly and higher doses are needed to achieve the desired effects. As mentioned earlier, some users are getting into patterns of compulsive binges.

This can lead to problems with memory, word/name recall, reduced attention span, damage to relationships, loss of productivity, isolation, and neglecting other interests. Despite evidence of harm the compulsive user often finds it difficult to cut down, all the hallmarks of dependence.

Distressing psychological effects of using ketamine

• Anxiety and panic attacks
• Depression and suicidal thoughts
• Insomnia and sleep disturbances (including nightmares)
• Flashbacks and persistent perceptual changes
• Feelings of unreality or detachment from the world (depersonalisation, derealisation)
• Paranoia

Bladder damage from ketamine use

There is clear evidence that heavy ketamine use can cause serious physical damage to the bladder and urinary tract. Some users develop a condition known as ulcerative cystitis, with symptoms such as:

• a frequent and urgent need to urinate
• pain or burning during urination
• blood in the urine
• urinary incontinence

These symptoms are linked to scarring and shrinking of the bladder. If ketamine use continues, the damage can become irreversible and may also lead to kidney problems.

For more on bladder-related complications, see our harm reduction page on ketamine bladder symptoms, k cramps & what to do about them.

What are K-cramps?

K-cramps (also called K-pains) refer to severe abdominal pain experienced by many people who use ketamine heavily. The exact cause is not fully understood, but is believed to involve irritation or damage to the gastrointestinal tract and gallbladder, and may also be linked to bladder-related complications.

K-cramps are most commonly reported by people taking high doses (such as more than a gram a day) or using ketamine daily. However, some people experience symptoms with frequent or prolonged use even at lower doses.

Is ketamine illegal?

Ketamine is illegal. Under the Misuse of Drugs Act (1971) it is a Class B drug. The maximum penalty for possession is five years in jail plus an unlimited fine. The maximum penalty for supplying to another person (dealing or giving away) is 14 years imprisonment plus an unlimited fine.

If you support people who use ketamine this is how you can help

The law

Let’s take that last point first. Ketamine is illegal. If the client wants to avoid the risk of arrest, prosecution, fine, jail or a criminal record – don’t go near ketamine. Simple. All ketamine users should be made aware of the legal risks they run.

Engagement

It is quite likely that mainstream drug services will not see ketamine users presenting for help. This is due, in part, to services being set up to deal with other drugs and are not geared towards the needs of ketamine users. This will also be the perception of ketamine users who don’t see themselves in the same league as heroin or crack users and may feel unwilling to attend such a service.

Contact is more likely to be made through advertising, in the appropriate places, your agency as a more broad-based service, ready and willing to support all forms of drug user. It is not the drug that is important but the behaviour. If you can get this across you may attract a more diverse clientele.

Even more effective will be outreach workers who can get to know ketamine users on their own terms. This approach has proved useful in many areas and helps to provide a bridge into mainstream provision. Outreach workers can also act as an early warning system, picking up on new trends developing in the community before individuals arrive on your doorstep needing help.

If you don’t currently have an outreach team, get one.

Education

Making ketamine users aware of the potential risks, particularly when mixed with other drugs, and ways of reducing harm is vital. How this information is put across will also determine the uptake of the service. Unrealistic, scaremongering will put people off, whereas honest, non-sensational, culturally attuned awareness raising will engage more effectively.

But, to be effective, it’s the credibility of the sender rather than the message itself that is often more important. If your agency has a user-friendly, non-punitive reputation in the community then individuals will feel more comfortable about coming forward. This is where outreach, again, can prove useful. Outreach workers can gain the trust of clients and explain what your service has to offer, as well as providing advice and information at the point of contact.

Vulnerability

Friends shouldn’t need reminding that, on a night out, they must look after each other. Even so, it’s worth reinforcing the message that if someone is really out of it they are vulnerable to all kinds of danger.

So make a plan before going out – stick together, agree meeting places if you get separated, before you go out order a taxi to pick you all up afterwards, make sure everyone has got each other’s phone numbers, try to keep tabs on who has taken what and how much. If someone is really out of it they should never be left alone or put in a taxi to be taken home on their own. They may not be in a fit state to make rational decisions, so they should not go off with their new ‘best friends’.

This may sound improbable, and boring, but if it’s not discussed no-one will think about it.

Collapse and unconsciousness

All drug users need to know how to react if someone collapses and this is important knowledge that you can pass on. Because of the ‘sledging’ effects of ketamine, this may prove very important.

Simple First Aid techniques (recovery position, stay with them + call an ambulance), applied at the point of need, saves a lot of bother. If you don’t currently teach First Aid to your clients, see about setting something up.

Compulsive use

Remember, it’s the behaviour not the drug. Some ketamine users find the escape from reality is a relief from feelings or memories they can’t control, in the same way that users of heroin, for example, find solace in the numbness that drug brings.

Clients who feel they can’t control their ketamine use are no different from the alcohol or heroin user who feels they can’t control their use either. An experienced worker will know where to use a brief intervention, how to assess need, or when to suggest more in-depth interventions such as CBT or MI.

Brief interventions, such as quantifying consumption, exploring the pros and cons of using or keeping a diary of use, has been shown to be very effective in reducing alcohol consumption. It has been used successfully with other drugs, so why not ketamine? Helping a client to define their frequency and level of use, and the gains to be made by cutting down, can help to break up patterns of consumption.

Cognitive Behavioural Therapy (CBT) has been used successfully in helping clients understand their motivation to use other drugs and could be equally applied to ketamine. Understanding how patterns of behaviour develop, identifying cues and triggers that stimulate the desire to use, and devising strategies to cope with high-risk situations can all help to bring about change.

And change is the goal. If a client is concerned enough about some aspects of their ketamine use, a Motivational Interviewing (MI) approach can help to identify how change can be incorporated into behaviour. Maintaining that change over time will help move the client through the process and into a less harmful situation.

Mental health

Ketamine has profound psychological effects. It can take the user to some very strange places inside their own head. If they do have unpleasant or suppressed memories, or do have an underlying or overt mental health issue then ketamine could exacerbate these. If the client does have a bad experience they should stop using ketamine immediately. If something has come to the surface that won’t go away, they should seek help from their GP.

Most people who have a bad, transitory ketamine experience will return to normal and will have learned an important lesson - Ketamine is an interesting place to visit, but you wouldn’t want to live there. For many, this will help them re-evaluate the desire for a trip to the dark side and possibly deter them in future.

Physical health

Most of the physical problems associated with ketamine are due to accidents whilst under the influence. At high doses, numbness in the extremities (mainly fingers and toes) is not unusual, but this might mask a broken bone that does not become apparent until the ketamine wears off. Looking after each other when on a night out is good advice, but if everyone’s in the K-hole it’s not much use. In the event of an accident or fall, making others (bar staff, security, First Aiders, etc.) aware that ketamine has been used could help avoid major injuries going unnoticed.

As stated above, some heavy users of ketamine have developed bladder problems. If any of the symptoms outlined above are experienced, it makes good sense to stop using ketamine altogether and seek medical advice. As for K-cramps, even though the exact cause is unclear it has been suggested that Tyrosine, used only under medical supervision, can help alleviate the pain.

This content is provided for harm reduction and educational purposes and is not a substitute for professional medical advice.

Please share this guide with people who use ketamine, their friends and families, and other professionals who may find it helpful.

Order ketamine leaflets and booklets to use with your service users.